Brain Volume Differences Associated With Hearing Impairment in Adults

PubMed Central

Vriend, Chris; Heslenfeld, Dirk J.; Versfeld, Niek J.; Kramer, Sophia E.

2018-01-01

Speech comprehension depends on the successful operation of a network of brain regions. Processing of degraded speech is associated with different patterns of brain activity in comparison with that of high-quality speech. In this exploratory study, we studied whether processing degraded auditory input in daily life because of hearing impairment is associated with differences in brain volume. We compared T1-weighted structural magnetic resonance images of 17 hearing-impaired (HI) adults with those of 17 normal-hearing (NH) controls using a voxel-based morphometry analysis. HI adults were individually matched with NH adults based on age and educational level. Gray and white matter brain volumes were compared between the groups by region-of-interest analyses in structures associated with speech processing, and by whole-brain analyses. The results suggest increased gray matter volume in the right angular gyrus and decreased white matter volume in the left fusiform gyrus in HI listeners as compared with NH ones. In the HI group, there was a significant correlation between hearing acuity and cluster volume of the gray matter cluster in the right angular gyrus. This correlation supports the link between partial hearing loss and altered brain volume. The alterations in volume may reflect the operation of compensatory mechanisms that are related to decoding meaning from degraded auditory input. PMID:29557274

Experimental study of the effect of polyanionic cellulose on process of filtrate loss of low-solids drilling fluid

NASA Astrophysics Data System (ADS)

yang, P.

2013-12-01

Experimental study of the effect of polyanionic cellulose on process of filtrate loss of low-solids drilling fluid Ping Yang 1,2, Min-hui Wu2, Xue-wen Zhu2, Tao Deng2, Xue-qing Sun2 1. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education, Tongji University, Shanghai 200092,China 2. Department of Geotechnical Engineering,Tongji University,Shanghai 200092,China Abstract The process of filtrate loss of low-solids drilling fluid was tested by changing the polyanionic cellulose content in low-solids drilling fluid. The effect of polyanionic cellulose on process of filtrate loss of low-solids drilling fluid was analyzed. The test results showed that when time of filtration is same, the volume of filtrate loss decreases linearly with increasing polyanionic cellulose content. When polyanionic cellulose content is same, the rate of filtrate loss decreases nonlinearly with increasing time and the rate of filtrate loss will reach a stable value.The volume of filtrate loss in 7 to 8 minutes can reaches half of the total volume of filtrate loss. At the same time, the rate of filtrate loss of drilling fluid decreases nonlinearly with increasing viscosity.When the apparent viscosity is between 3.5~4.15 MPa.s, decrease speed of rate of filtrate loss of drilling fluid is quick. The results are helpful for characteristics evaluation of filtrate loss of drilling fluid and control of filtrate loss. Keyword Polyanionic Cellulose,Drilling Fluid,Process of Filtrate Loss Acknowledgments This investigation was supported by the National Natural Science Foundation of China (projects No. 41002093 and 41072205); the Fundamental Research Funds for the Central Universities; the Shanghai Leading Academic Discipline Project (project No. B308), Tongji University; and the Program for Young Excellent Talents, Tongji University. The authors are extremely grateful for the financial support from these five organizations.

Disc size regulation in the brood cell building behavior of leaf-cutter bee, Megachile tsurugensis

NASA Astrophysics Data System (ADS)

Kim, Jong-Yoon

2007-12-01

The leaf-cutter bee, Megachile tsurugensis, builds a brood cell in a preexisting tunnel with leaf discs that she cuts in decreasing sizes and assembles them like a Russian matryoshka doll. By experimentally manipulating the brood cell, it was investigated how she regulates the size of leaf discs that fit in the brood cell’s internal volume. When the internal volume was artificially increased by removing a bulk of leaf discs, she decreased the leaf disc size, although increasing it would have made the leaf disc more fitting in the increased internal volume. As a reverse manipulation, when the internal volume was decreased by inserting a group of inner layers of preassembled leaf discs to a brood cell, she decreased the leaf disc size, so that the leaf disc could fit in the decreased internal volume. These results suggest that she uses at least two different mechanisms to regulate the disc size: the use of some internal memory about the degree of building work accomplished in the first and of sensory feedback of dimensional information at the construction site in the second manipulation, respectively. It was concluded that a stigmergic mechanism, an immediate sensory feedback from the brood cell changed by the building work, alone cannot explain the details of the bee’s behavior particularly with respect to her initial response to the first manipulation. For a more complete explanation of the behavior exhibited by the solitary bee, two additional behavioral elements, reinforcement of building activity and processing of dimensional information, were discussed along with stigmergy.

Disc size regulation in the brood cell building behavior of leaf-cutter bee, Megachile tsurugensis.

PubMed

Kim, Jong-yoon

2007-12-01

The leaf-cutter bee, Megachile tsurugensis, builds a brood cell in a preexisting tunnel with leaf discs that she cuts in decreasing sizes and assembles them like a Russian matryoshka doll. By experimentally manipulating the brood cell, it was investigated how she regulates the size of leaf discs that fit in the brood cell's internal volume. When the internal volume was artificially increased by removing a bulk of leaf discs, she decreased the leaf disc size, although increasing it would have made the leaf disc more fitting in the increased internal volume. As a reverse manipulation, when the internal volume was decreased by inserting a group of inner layers of preassembled leaf discs to a brood cell, she decreased the leaf disc size, so that the leaf disc could fit in the decreased internal volume. These results suggest that she uses at least two different mechanisms to regulate the disc size: the use of some internal memory about the degree of building work accomplished in the first and of sensory feedback of dimensional information at the construction site in the second manipulation, respectively. It was concluded that a stigmergic mechanism, an immediate sensory feedback from the brood cell changed by the building work, alone cannot explain the details of the bee's behavior particularly with respect to her initial response to the first manipulation. For a more complete explanation of the behavior exhibited by the solitary bee, two additional behavioral elements, reinforcement of building activity and processing of dimensional information, were discussed along with stigmergy.

[Effect on the respiration of bacteria in microcosm by the disinfectant of chlorine].

PubMed

Lu, Yi; Wang, Ying; Ren, Lijun; Wang, Lin

2007-03-01

To observe respiratory volume of bacteria as the physiology activity index to evaluate the effect of sodium hypochlorite (NaClO) on the microenvironment. The water and soil from Wuhan Muoshui Lake were selected as research object. Man-made microcosms were designed and constructed. The sodium hypochlorite was put into the microcosms every 24 hour for 13 days. The bacteria respiratory volume and the general bacterial population were observed. The results showed that the bacteria in the low-dose disinfectant were stimulated and its respiration volumes were increased in the beginning of the experiment. But several days later, the bacteria were inhibited or killed predominantly which led to the decrease of its respiration volumes. In high-dose group, the bacteria were killed obviously in the beginning and their respiration volumes decreased immediately. After the disinfectant was given up, the respiratory volume resumed gradually to the initial condition. This change process accorded with the general bacterial population as a whole. The respiratory volume of bacteria was related with the dose of disinfectant. The change of the respiratory volume of bacteria was related with the dose of sodium hypochlorite. The disinfectant effect on the metabolic activity of microorganism would be lighter if it under the dose 10 mg/L.

Biometric analysis of pigment dispersion syndrome using anterior segment optical coherence tomography.

PubMed

Aptel, Florent; Beccat, Sylvain; Fortoul, Vincent; Denis, Philippe

2011-08-01

To compare anterior chamber volume (ACV), iris volume, and iridolenticular contact (ILC) area before and after laser peripheral iridotomy (LPI) in eyes with pigment dispersion syndrome (PDS) using anterior segment optical coherence tomography (AS OCT) and image processing software. Cross-sectional study. Eighteen eyes of 18 patients with PDS; 30 eyes of 30 controls matched for age, gender, and refraction. Anterior segment OCT imaging was performed in all eyes before LPI and 1, 4, and 12 weeks after LPI. At each visit, 12 cross-sectional images of the AS were taken: 4 in bright conditions with accommodation (accommodation), 4 in bright conditions without accommodation (physiological miosis), and 4 under dark conditions (physiologic mydriasis). Biometric parameters were estimated using AS OCT radial sections and customized image-processing software. Anterior chamber volume, iris volume-to-length ratio, ILC area, AS OCT anterior chamber depth, and A-scan ultrasonography axial length. Before LPI, PDS eyes had a significantly greater ACV and ILC area than control eyes (P<0.01) and a significantly smaller iris volume-to-length ratio than the controls (P<0.05). After LPI, ACV and ILC area decreased significantly in PDS eyes, but iris volume-to-length ratio increased significantly (P<0.02) and was not significantly different from that of controls. These biometric changes were stable over time. Iris volume-to-length ratio decreased significantly from accommodation to mydriasis and from miosis to mydriasis, both in PDS and control eyes (P<0.01). In PDS eyes, ILC area decreased significantly from accommodation to mydriasis, both before and after LPI (P<0.01). On multivariate analysis, greater anterior chamber (AC) volume (P<0.02) and larger AC depth (P<0.05) before LPI were significant predictors of a larger ILC area. Pigment dispersion syndrome eyes do not have an iris that is abnormally large, relative to the AS size, but have a weakly resistant iris that is stretched and pushed against the lens when there is a pressure difference across the iris. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Lung volume quantified by MRI reflects extracellular-matrix deposition and altered pulmonary function in bleomycin models of fibrosis: effects of SOM230.

PubMed

Egger, Christine; Gérard, Christelle; Vidotto, Nella; Accart, Nathalie; Cannet, Catherine; Dunbar, Andrew; Tigani, Bruno; Piaia, Alessandro; Jarai, Gabor; Jarman, Elizabeth; Schmid, Herbert A; Beckmann, Nicolau

2014-06-15

Idiopathic pulmonary fibrosis is a progressive and lethal disease, characterized by loss of lung elasticity and alveolar surface area, secondary to alveolar epithelial cell injury, reactive inflammation, proliferation of fibroblasts, and deposition of extracellular matrix. The effects of oropharyngeal aspiration of bleomycin in Sprague-Dawley rats and C57BL/6 mice, as well as of intratracheal administration of ovalbumin to actively sensitized Brown Norway rats on total lung volume as assessed noninvasively by magnetic resonance imaging (MRI) were investigated here. Lung injury and volume were quantified by using nongated or respiratory-gated MRI acquisitions [ultrashort echo time (UTE) or gradient-echo techniques]. Lung function of bleomycin-challenged rats was examined additionally using a flexiVent system. Postmortem analyses included histology of collagen and hydroxyproline assays. Bleomycin induced an increase of MRI-assessed total lung volume, lung dry and wet weights, and hydroxyproline content as well as collagen amount. In bleomycin-treated rats, gated MRI showed an increased volume of the lung in the inspiratory and expiratory phases of the respiratory cycle and a temporary decrease of tidal volume. Decreased dynamic lung compliance was found in bleomycin-challenged rats. Bleomycin-induced increase of MRI-detected lung volume was consistent with tissue deposition during fibrotic processes resulting in decreased lung elasticity, whereas influences by edema or emphysema could be excluded. In ovalbumin-challenged rats, total lung volume quantified by MRI remained unchanged. The somatostatin analog, SOM230, was shown to have therapeutic effects on established bleomycin-induced fibrosis in rats. This work suggests MRI-detected total lung volume as readout for tissue-deposition in small rodent bleomycin models of pulmonary fibrosis. Copyright © 2014 the American Physiological Society.

[Fractal features of soil particle size in the process of desertification in desert grassland of Ningxia, China].

PubMed

Yan, Xin; An, Hui

2017-10-01

The variation of soil properties, the fractal dimension of soil particle size, and the relationships between fractal dimension of soil particle size and soil properties in the process of desertification in desert grassland of Ningxia were discussed. The results showed that the fractal dimension (D) at different desertification stages in desert grassland varied greatly, the value of D was between 1.69 and 2.62. Except for the 10-20 cm soil layer, the value of D gradually declined with increa sing desertification of desert grassland at 0-30 cm soil layer. In the process of desertification in de-sert grassland, the grassland had the highest values of D , the volume percentage of clay and silt, and the lowest values of the volume percentage of very fine sand and fine sand. However, the mobile dunes had the lowest value of D , the volume percentage of clay and silt, and the highest value of the volume percentage of very fine sand and fine sand. There was a significant positive correlation between the soil fractal dimension value and the volume percentage of soil particles <50 μm, and a significant negative correlation between the soil fractal dimension value and the volume percentage of soil particles >50 μm. The grain size of 50 μm was the critical value for deciding the relationship between the soil particle fractal dimension and the volume percentage. Soil organic matter (SOM) and total nitrogen (TN) decreased gradually with increasing desertification of desert grassland, but soil bulk density increased gradually. Qualitative change from fixed dunes to semi fixed dunes with the rapid decrease of the volume percentage of clay and silt, SOM, TN and the rapid increase of volume percentage of very fine sand and fine sand, soil bulk density. Fractal dimension was significantly correlated to SOM, TN and soil bulk density. Fractal dimension 2.58 was a critical value of fixed dunes and semi fixed dunes. So, the fractal dimension of 2.58 could be taken as the desertification indicator of desert grassland.

Visuomotor Binding in Older Adults

ERIC Educational Resources Information Center

Bloesch, Emily K.; Abrams, Richard A.

2010-01-01

Action integration is the process through which actions performed on a stimulus and perceptual aspects of the stimulus become bound as a unitary object. This process appears to be controlled by the dopaminergic system in the prefrontal cortex, an area that is known to decrease in volume and dopamine functioning in older adults. Although the…

Intracranial volume, cranial thickness, and hyperostosis frontalis interna in the elderly.

PubMed

May, Hila; Mali, Yael; Dar, Gali; Abbas, Janan; Hershkovitz, Israel; Peled, Nathan

2012-01-01

According to the "brain reserve hypothesis," a larger premorbid brain protects against the development of dementia. The aim of this study was to reveal a possible pathophysiology of brain degenerative diseases by studying intracranial bone lesions that act to reduce intracranial volume (ICV), such as hyperostosis frontalis interna (HFI). Three hundred and eighty postmenopausal females (aged 60+) who had undergone a head computerized tomography scan (Brilliance 64, Philips Healthcare, Cleveland, OH) at the Carmel Medical Center, Haifa, Israel, before the study were included. The subjects were divided into four groups according to their degree of HFI. Six measurements of the skull and brain were taken. As HFI becomes more severe, the cranial bone thickness and cranial bone volume increase. This process is accompanied by a decrease in ICV. In none of the HFI groups studied there was a significant association between ICV and cranial bone thickness. The inter-relationships between the various thickness parameters are not disturbed by the degree of HFI. HFI is accompanied by an increase in thickness of all calvarial bones and reduced ICV. In addition, the thickening process initiated by HFI is synchronized among the calvarial bones. Presence of HFI suggests a decrease in brain volume and has a major clinical significance as it may indicate the beginning of degenerative processes of the brain. In addition, as females age, their skulls tend to develop more robust characteristics. Copyright © 2012 Wiley Periodicals, Inc.

Effect of egg freshness on texture and baking characteristics of batter systems formulated using egg, flour and sugar.

PubMed

Xing, Liting; Niu, Fuge; Su, Yujie; Yang, Yanjun

2016-04-01

The aim of this work was to evaluate the effects of egg freshness on baking properties and final qualities in batter systems. Batters were made with eggs of different freshness, and the properties of batter systems were studied through rheological analysis, rapid viscosity analysis (RVA), differential scanning calorimetry (DSC), batter density and expansion rate during the baking and cooling processes. Moreover, the qualities of final baked systems were investigated, including specific volume and texture profile analysis (TPA). The flow behavior of batters showed that the consistency index (K) decreased as the Haugh unit (HU) value decreased, while the flow behavior index (n) increased. Both the storage modulus (G') and loss modulus (G″) determined by mechanical spectra at 20 °C decreased with decreasing HU. RVA and DSC determinations revealed that lower-HU samples had a lower viscosity in the baking process and a shorter time for starch gelatinization and egg protein denaturation. Observation of the batter density revealed an increasing change, which was reflected by a decrease in the specific volume of final models. TPA showed significant differences in hardness and chewiness, but no significant differences in springiness and cohesiveness were found. The egg freshness affected the properties of batter systems. © 2015 Society of Chemical Industry.

Whole brain volume changes and its correlation with clinical symptom severity in patients with schizophrenia: A DARTEL-based VBM study.

PubMed

Kim, Gwang-Won; Kim, Yun-Hyeon; Jeong, Gwang-Woo

2017-01-01

The purpose of this study was to evaluate gray matter (GM) and white matter (WM) volume alterations in whole-brain structures in patients with schizophrenia and healthy controls using voxel-based morphometry (VBM), and further to assess the correlation between GM and WM volume variations and symptom severity in schizophrenia. A total of 22 patients with schizophrenia and 22 age-matched healthy controls participated. Magnetic resonance image data were processed using SPM8 software with diffeomorphic anatomical registration via an exponentiated Lie algebra (DARTEL) algorithm. Patients with schizophrenia exhibited significantly decreased GM volumes of the insula, superior temporal gyrus (STG), gyrus rectus, and anterior cingulate cortex (ACC) compared with healthy controls. The GM volumes of the STG and gyrus rectus were negatively correlated with the positive scales on the Positive and Negative Syndrome Scale (PANSS) and those of the STG and ACC were negatively correlated with the negative scales. The durations of illness in schizophrenia were negatively correlated with the GM volumes of the insula, STG, and ACC. Patients with schizophrenia exhibited significantly decreased WM volumes of the superior frontal gyrus, inferior temporal gyrus, and STG. The WM volumes of the STG were negatively correlated with the duration of illness. Our findings suggest that GM and WM volume abnormalities in the STG are associated with the psychopathology of schizophrenia.

Sparse aperture endoscope

DOEpatents

Fitch, J.P.

1999-07-06

An endoscope is disclosed which reduces the volume needed by the imaging part, maintains resolution of a wide diameter optical system, while increasing tool access, and allows stereographic or interferometric processing for depth and perspective information/visualization. Because the endoscope decreases the volume consumed by imaging optics such allows a larger fraction of the volume to be used for non-imaging tools, which allows smaller incisions in surgical and diagnostic medical applications thus produces less trauma to the patient or allows access to smaller volumes than is possible with larger instruments. The endoscope utilizes fiber optic light pipes in an outer layer for illumination, a multi-pupil imaging system in an inner annulus, and an access channel for other tools in the center. The endoscope is amenable to implementation as a flexible scope, and thus increases it's utility. Because the endoscope uses a multi-aperture pupil, it can also be utilized as an optical array, allowing stereographic and interferometric processing. 7 figs.

Sparse aperture endoscope

DOEpatents

Fitch, Joseph P.

1999-07-06

An endoscope which reduces the volume needed by the imaging part thereof, maintains resolution of a wide diameter optical system, while increasing tool access, and allows stereographic or interferometric processing for depth and perspective information/visualization. Because the endoscope decreases the volume consumed by imaging optics such allows a larger fraction of the volume to be used for non-imaging tools, which allows smaller incisions in surgical and diagnostic medical applications thus produces less trauma to the patient or allows access to smaller volumes than is possible with larger instruments. The endoscope utilizes fiber optic light pipes in an outer layer for illumination, a multi-pupil imaging system in an inner annulus, and an access channel for other tools in the center. The endoscope is amenable to implementation as a flexible scope, and thus increases the utility thereof. Because the endoscope uses a multi-aperture pupil, it can also be utilized as an optical array, allowing stereographic and interferometric processing.

A Comparison of Two Fat Grafting Methods on Operating Room Efficiency and Costs.

PubMed

Gabriel, Allen; Maxwell, G Patrick; Griffin, Leah; Champaneria, Manish C; Parekh, Mousam; Macarios, David

2017-02-01

Centrifugation (Cf) is a common method of fat processing but may be time consuming, especially when processing large volumes. To determine the effects on fat grafting time, volume efficiency, reoperations, and complication rates of Cf vs an autologous fat processing system (Rv) that incorporates fat harvesting and processing in a single unit. We performed a retrospective cohort study of consecutive patients who underwent autologous fat grafting during reconstructive breast surgery with Rv or Cf. Endpoints measured were volume of fat harvested (lipoaspirate) and volume injected after processing, time to complete processing, reoperations, and complications. A budget impact model was used to estimate cost of Rv vs Cf. Ninety-eight patients underwent fat grafting with Rv, and 96 patients received Cf. Mean volumes of lipoaspirate (506.0 vs 126.1 mL) and fat injected (177.3 vs 79.2 mL) were significantly higher (P < .0001) in the Rv vs Cf group, respectively. Mean time to complete fat grafting was significantly shorter in the Rv vs Cf group (34.6 vs 90.1 minutes, respectively; P < .0001). Proportions of patients with nodule and cyst formation and/or who received reoperations were significantly less in the Rv vs Cf group. Based on these outcomes and an assumed per minute operating room cost, an average per patient cost savings of $2,870.08 was estimated with Rv vs Cf. Compared to Cf, the Rv fat processing system allowed for a larger volume of fat to be processed for injection and decreased operative time in these patients, potentially translating to cost savings. LEVEL OF EVIDENCE 3. © 2016 The American Society for Aesthetic Plastic Surgery, Inc.

Impacts of simultaneous multislice acquisition on sensitivity and specificity in fMRI.

PubMed

Risk, Benjamin B; Kociuba, Mary C; Rowe, Daniel B

2018-05-15

Simultaneous multislice (SMS) imaging can be used to decrease the time between acquisition of fMRI volumes, which can increase sensitivity by facilitating the removal of higher-frequency artifacts and boosting effective sample size. The technique requires an additional processing step in which the slices are separated, or unaliased, to recover the whole brain volume. However, this may result in signal "leakage" between aliased locations, i.e., slice "leakage," and lead to spurious activation (decreased specificity). SMS can also lead to noise amplification, which can reduce the benefits of decreased repetition time. In this study, we evaluate the original slice-GRAPPA (no leak block) reconstruction algorithm and acceleration factor (AF = 8) used in the fMRI data in the young adult Human Connectome Project (HCP). We also evaluate split slice-GRAPPA (leak block), which can reduce slice leakage. We use simulations to disentangle higher test statistics into true positives (sensitivity) and false positives (decreased specificity). Slice leakage was greatly decreased by split slice-GRAPPA. Noise amplification was decreased by using moderate acceleration factors (AF = 4). We examined slice leakage in unprocessed fMRI motor task data from the HCP. When data were smoothed, we found evidence of slice leakage in some, but not all, subjects. We also found evidence of SMS noise amplification in unprocessed task and processed resting-state HCP data. Copyright © 2018 Elsevier Inc. All rights reserved.

Influence of primary α-phase volume fraction on the mechanical properties of Ti-6Al-4V alloy at different strain rates and temperatures

NASA Astrophysics Data System (ADS)

Ren, Yu; Zhou, Shimeng; Luo, Wenbo; Xue, Zhiyong; Zhang, Yajing

2018-03-01

Bimodal microstructures with primary α-phase volume fractions ranging from 14.3% to 57.1% were gained in Ti-6Al-4V (Ti-64) alloy through annealed in two-phase region at various temperatures below the β-transus point. Then the influence of the primary α-phase volume fraction on the mechanical properties of Ti-64 were studied. The results show that, at room temperature and a strain rate of 10‑3 s‑1, the yield stress decreases but the fracture strain augments with added primary α-phase volume fraction. The equiaxed primary α-phase possesses stronger ability to coordinate plastic deformation, leading to the improvement of the ductile as well as degradation of the strength of Ti-64 with higher primary α-phase volume fraction. As the temperature goes up to 473 K, the quasi-static yield stress and ultimate strength decrease first and then increase with the incremental primary α-phase volume fraction, due to the interaction between the work hardening and the softening caused by the DRX and the growth of the primary α-phase. At room temperature and a strain rate of 3×103 s‑1, the varying pattern of strength with the primary α-phase volume fraction resembles that at a quasi-static strain rate. However, the flow stress significantly increases but the strain-hardening rate decreases compared to those at quasi-static strain rate due to the competition between the strain rate hardening and the thermal softening during dynamic compression process.

Effects of large volume injection of aliphatic alcohols as sample diluents on the retention of low hydrophobic solutes in reversed-phase liquid chromatography.

PubMed

David, Victor; Galaon, Toma; Aboul-Enein, Hassan Y

2014-01-03

Recent studies showed that injection of large volume of hydrophobic solvents used as sample diluents could be applied in reversed-phase liquid chromatography (RP-LC). This study reports a systematic research focused on the influence of a series of aliphatic alcohols (from methanol to 1-octanol) on the retention process in RP-LC, when large volumes of sample are injected on the column. Several model analytes with low hydrophobic character were studied by RP-LC process, for mobile phases containing methanol or acetonitrile as organic modifiers in different proportions with aqueous component. It was found that starting with 1-butanol, the aliphatic alcohols can be used as sample solvents and they can be injected in high volumes, but they may influence the retention factor and peak shape of the dissolved solutes. The dependence of the retention factor of the studied analytes on the injection volume of these alcohols is linear, with a decrease of its value as the sample volume is increased. The retention process in case of injecting up to 200μL of upper alcohols is dependent also on the content of the organic modifier (methanol or acetonitrile) in mobile phase. Copyright © 2013 Elsevier B.V. All rights reserved.

Lightweight armor system and process for producing the same

DOEpatents

Chu, Henry S.; Bruck, H. Alan; Strempek, Gary C.; Varacalle, Jr., Dominic J.

2004-01-20

A lightweight armor system may comprise a substrate having a graded metal matrix composite layer formed thereon by thermal spray deposition. The graded metal matrix composite layer comprises an increasing volume fraction of ceramic particles imbedded in a decreasing volume fraction of a metal matrix as a function of a thickness of the graded metal matrix composite layer. A ceramic impact layer is affixed to the graded metal matrix composite layer.

Impaired Recognition and Regulation of Disgust Is Associated with Distinct but Partially Overlapping Patterns of Decreased Gray Matter Volume in the Ventroanterior Insula.

PubMed

Woolley, Josh D; Strobl, Eric V; Sturm, Virginia E; Shany-Ur, Tal; Poorzand, Pardis; Grossman, Scott; Nguyen, Lauren; Eckart, Janet A; Levenson, Robert W; Seeley, William W; Miller, Bruce L; Rankin, Katherine P

2015-10-01

The ventroanterior insula is implicated in the experience, expression, and recognition of disgust; however, whether this brain region is required for recognizing disgust or regulating disgusting behaviors remains unknown. We examined the brain correlates of the presence of disgusting behavior and impaired recognition of disgust using voxel-based morphometry in a sample of 305 patients with heterogeneous patterns of neurodegeneration. Permutation-based analyses were used to determine regions of decreased gray matter volume at a significance level p <= .05 corrected for family-wise error across the whole brain and within the insula. Patients with behavioral variant frontotemporal dementia and semantic variant primary progressive aphasia were most likely to exhibit disgusting behaviors and were, on average, the most impaired at recognizing disgust in others. Imaging analysis revealed that patients who exhibited disgusting behaviors had significantly less gray matter volume bilaterally in the ventral anterior insula. A region of interest analysis restricted to behavioral variant frontotemporal dementia and semantic variant primary progressive aphasia patients alone confirmed this result. Moreover, impaired recognition of disgust was associated with decreased gray matter volume in the bilateral ventroanterior and ventral middle regions of the insula. There was an area of overlap in the bilateral anterior insula where decreased gray matter volume was associated with both the presence of disgusting behavior and impairments in recognizing disgust. These findings suggest that regulating disgusting behaviors and recognizing disgust in others involve two partially overlapping neural systems within the insula. Moreover, the ventral anterior insula is required for both processes. Published by Elsevier Inc.

Impaired recognition and regulation of disgust is associated with distinct but partially overlapping patterns of decreased gray matter volume in the ventroanterior insula

PubMed Central

Woolley, Joshua; Strobl, Eric V; Sturm, Virginia E; Shany-Ur, Tal; Poorzand, Pardis; Grossman, Scott; Nguyen, Lauren; Eckart, Janet A; Levenson, Robert W; Seeley, William W; Miller, Bruce L; Rankin, Katherine P

2015-01-01

Background The ventroanterior insula is implicated in the experience, expression, and recognition of disgust; however, whether this brain region is required for recognizing disgust or regulating disgusting behaviors remains unknown. Methods We examined the brain correlates of the presence of disgusting behavior and impaired recognition of disgust using voxel-based morphometry in a sample of 305 patients with heterogeneous patterns of neurodegeneration. Permutation-based analyses were used to determine regions of decreased grey matter volume at a significance level p<0.05 corrected for family-wise error across the whole brain and within the insula. Results Patients with behavioral variant frontotemporal dementia (bvFTD) and semantic variant primary progressive aphasia (svPPA) were most likely to exhibit disgusting behaviors and were, on average, the most impaired at recognizing disgust in others. Imaging analysis revealed that patients who exhibited disgusting behaviors had significantly less grey matter volume bilaterally in the ventral anterior insula. A region of interest analysis restricted to bvFTD and svPPA patients alone confirmed this result. Moreover, impaired recognition of disgust was associated with decreased grey matter volume in the bilateral ventroanterior and ventral middle regions of the insula. There was an area of overlap in the bilateral anterior insula where decreased grey matter volume was associated with both the presence of disgusting behavior and impairments in recognizing disgust. Conclusion These findings suggest that regulating disgusting behaviors and recognizing disgust in others involve two partially overlapping neural systems within the insula. Moreover, the ventral anterior insula is required for both processes. PMID:25890642

Stereolithographic volume evaluation of healing and shaping after rhinoplasty operations.

PubMed

Tatlidede, Soner; Turgut, Gürsel; Gönen, Emre; Kayali, Mahmut Ulvi; Baş, Lütfü

2009-07-01

Nasal edema and volume changes are unavoidable processes during the healing period after rhinoplasty. Various applications were reported regarding the prevention of early edema; however, the literature shows no study focused on the course of the nasal edema and volume changes up-to-date. We aimed to study the nasal volume changes during the first year of postoperative healing period and to form a recovery and volume change diagram with the obtained data. We prepared standard frames and nasal molds of 7 rhinoplasty patients at regular time intervals (preoperative period and at the postoperative 1st, 2nd, 4th, 8th, 12th, 24th, and 52nd weeks). Plaster nasal models were created by using these molds. Volumes of models were measured by computed tomographic scanning and three-dimensional image processing programs. According to our results, the nasal edema reaches its maximum level at the postoperative fourth week and then rapidly decreases until its minimum level at the eighth week. In contrast with the general opinion, the nasal volume begins to increase smoothly reaching to a level minimally below the preoperative value by the end of the first year.

Application of a Model for Quenching and Partitioning in Hot Stamping of High-Strength Steel

NASA Astrophysics Data System (ADS)

Zhu, Bin; Liu, Zhuang; Wang, Yanan; Rolfe, Bernard; Wang, Liang; Zhang, Yisheng

2018-04-01

Application of quenching and partitioning process in hot stamping has proven to be an effective method to improve the plasticity of advanced high-strength steels (AHSSs). In this study, the hot stamping and partitioning process of advanced high-strength steel 30CrMnSi2Nb is investigated with a hot stamping mold. Given the specific partitioning time and temperature, the influence of quenching temperature on the volume fraction of microstructure evolution and mechanical properties of the above steel are studied in detail. In addition, a model for quenching and partitioning process is applied to predict the carbon diffusion and interface migration during partitioning, which determines the retained austenite volume fraction and final properties of the part. The predicted trends of the retained austenite volume fraction agree with the experimental results. In both cases, the volume fraction of retained austenite increases first and then decreases with the increasing quenching temperature. The optimal quenching temperature is approximately 290 °C for 30CrMnSi2Nb with the partition conditions of 425 °C and 20 seconds. It is suggested that the model can be used to help determine the process parameters to obtain retained austenite as much as possible.

Anti-aging and filling efficacy of six types hyaluronic acid based dermo-cosmetic treatment: double blind, randomized clinical trial of efficacy and safety.

PubMed

Nobile, Vincenzo; Buonocore, Daniela; Michelotti, Angela; Marzatico, Fulvio

2014-12-01

Human skin aging is a multifactorial and complex biological process affecting the different skin constituents. Even if the skin aging mechanism is not yet fully unravelled is evident that epidermis loses the principal molecule responsible for binding and retaining water molecules, resulting in loss of skin moisture and accounting for some of the most striking alterations of the aged skin. This Study investigated the cosmetic filling efficacy of Fillerina® in decreasing the skin aging signs and in improving facial volume deficiencies. A placebo-controlled, double-blind, randomized clinical trial was carried out on 40 healthy female subjects showing mild to moderate clinical signs of skin aging. The effect of the treatment on skin surface and on face volumes was assessed both in the short-term (3 h after a single product application) and in the long-term (7, 14, and 30 days after continuative daily use). Three hours after a single application and after 7, 14, and 30 days of treatment the lips volume was increased by 8.5%, 11.3%, 12.8%, and 14.2%. After 7, 14, and 30 days: (1) skin sagging of the face contours was decreased by -0.443 ± 0.286, -1.124 ± 0.511, and -1.326 ± 0.649 mm, respectively; (2) skin sagging of the cheekbones contours was decreased by -0.989 ± 0.585, -2.500 ± 0.929, and -2.517 ± 0.927 mm, respectively; (3) cheekbones volume was increased by 0.875 ± 0.519, 2.186 ± 0.781, and 2.275 ± 0.725 mm, respectively; (4) wrinkle volume was decreased by -11.3%, -18.4%, and -26.3%, respectively; and (5) wrinkle depth was decreased by -8.4%, -14.5%, and -21.8% respectively. This study demonstrated the positive filling effect of Fillerina® in decreasing the clinical signs of skin aging and in improving the face volumes. © 2014 Wiley Periodicals, Inc.

Redesigning a joint replacement program using Lean Six Sigma in a Veterans Affairs hospital.

PubMed

Gayed, Benjamin; Black, Stephen; Daggy, Joanne; Munshi, Imtiaz A

2013-11-01

In April 2009, an analysis of joint replacement surgical procedures at the Richard L. Roudebush Veterans Affairs Medical Center, Indianapolis, Indiana, revealed that total hip and knee replacements incurred $1.4 million in non-Veterans Affairs (VA) care costs with an average length of stay of 6.1 days during fiscal year 2008. The Joint Replacement Program system redesign project was initiated following the Vision-Analysis-Team-Aim-Map-Measure-Change-Sustain (VA-TAMMCS) model to increase efficiency, decrease length of stay, and reduce non-VA care costs. To determine the effectiveness of Lean Six Sigma process improvement methods applied in a VA hospital. Perioperative processes for patients undergoing total joint replacement were redesigned following the VA-TAMMCS model--the VA's official, branded method of Lean Six Sigma process improvement. A multidisciplinary team including the orthopedic surgeons, frontline staff, and executive management identified waste in the current processes and initiated changes to reduce waste and increase efficiency. Data collection included a 1-year baseline period and a 20-month sustainment period. The primary endpoint was length of stay; a secondary analysis considered non-VA care cost reductions. Length of stay decreased 36% overall, decreasing from 5.3 days during the preproject period to 3.4 days during the 20-month sustainment period (P < .001). Non-VA care was completely eliminated for patients undergoing total hip and knee replacement at the Richard L. Roudebush Veterans Affairs Medical Center, producing an estimated return on investment of $1 million annually when compared with baseline cost and volumes. In addition, the volume of total joint replacements at this center increased during the data collection period. The success of the Joint Replacement Program demonstrates that VA-TAMMCS is an effective tool for Lean and Six Sigma process improvement initiatives in a surgical practice, producing a 36% sustained reduction in length of stay and completely eliminating non-VA care for total hip and knee replacements while increasing total joint replacement volume at this medical center.

Structural mass irregularities and fiber volume influence on morphology and mechanical properties of unsaturated polyester resin in matrix composites

PubMed Central

Ahmed, Khalil; Nasir, Muhammad; Fatima, Nasreen; Khan, Khalid M.; Zahra, Durey N.

2014-01-01

This paper presents the comparative results of a current study on unsaturated polyester resin (UPR) matrix composites processed by filament winding method, with cotton spun yarn of different mass irregularities and two different volume fractions. Physical and mechanical properties were measured, namely ultimate stress, stiffness, elongation%. The mechanical properties of the composites increased significantly with the increase in the fiber volume fraction in agreement with the Counto model. Mass irregularities in the yarn structure were quantitatively measured and visualized by scanning electron microscopy (SEM). Mass irregularities cause marked decrease in relative strength about 25% and 33% which increases with fiber volume fraction. Ultimate stress and stiffness increases with fiber volume fraction and is always higher for yarn with less mass irregularities. PMID:26644920

Progressive Decrease of Left Heschl Gyrus and Planum Temporale Gray Matter Volume in First-Episode Schizophrenia

PubMed Central

Kasai, Kiyoto; Shenton, Martha E.; Salisbury, Dean F.; Hirayasu, Yoshio; Onitsuka, Toshiaki; Spencer, Magdalena H.; Yurgelun-Todd, Deborah A.; Kikinis, Ron; Jolesz, Ferenc A.; McCarley, Robert W.

2010-01-01

Background The Heschl gyrus and planum temporale have crucial roles in auditory perception and language processing. Our previous investigation using magnetic resonance imaging (MRI) indicated smaller gray matter volumes bilaterally in the Heschl gyrus and in left planum temporale in patients with first-episode schizophrenia but not in patients with first-episode affective psychosis. We sought to determine whether there are progressive decreases in anatomically defined MRI gray matter volumes of the Heschl gyrus and planum temporale in patients with first-episode schizophrenia and also in patients with first-episode affective psychosis. Methods At a private psychiatric hospital, we conducted a prospective high spatial resolution MRI study that included initial scans of 28 patients at their first hospitalization (13 with schizophrenia and 15 with affective psychosis, 13 of whom had a manic psychosis) and 22 healthy control subjects. Follow-up scans occurred, on average, 1.5 years after the initial scan. Results Patients with first-episode schizophrenia showed significant decreases in gray matter volume over time in the left Heschl gyrus (6.9%) and left planum temporale (7.2%) compared with patients with first-episode affective psychosis or control subjects. Conclusions These findings demonstrate a left-biased progressive volume reduction in the Heschl gyrus and planum temporale gray matter in patients with first-episode schizophrenia in contrast to patients with first-episode affective psychosis and control subjects. Schizophrenia but not affective psychosis seems to be characterized by a postonset progression of neocortical gray matter volume loss in the left superior temporal gyrus and thus may not be developmentally fixed. PMID:12912760

Human trabecular meshwork cell volume decrease by NO-independent soluble guanylate cyclase activators YC-1 and BAY-58-2667 involves the BKCa ion channel.

PubMed

Dismuke, William M; Sharif, Najam A; Ellis, Dorette Z

2009-07-01

There is a correlation between cell volume changes and changes in the rate of aqueous humor outflow; agents that decrease trabecular meshwork (TM) cell volume increase the rate of aqueous humor outflow. This study investigated the effects of the nitric oxide (NO)-independent activators of soluble guanylate cyclase (sGC), YC-1, and BAY-58-2667 on TM cell volume and the signal transduction pathways and ion channel involved. Cell volume was measured with the use of calcein AM fluorescent dye, detected by confocal microscopy. Inhibitors and activators of sGC, 3',5'-cyclic guanosine monophosphate (cGMP), protein kinase G (PKG), and the BK(Ca) channel were used to characterize their involvement in the YC-1- and BAY-58-2667-induced regulation of TM cell volume. cGMP was assayed by an enzyme immunoassay. YC-1 (10 nM-200 microM) and BAY-58-2667 (10 nM-100 microM) each elicited a biphasic effect on TM cell volume. YC-1 (1 microM) increased TM cell volume, but higher concentrations decreased TM cell volume. Similarly, BAY-58-2667 (100 nM) increased TM cell volume, but higher concentrations decreased cell volume. The YC-1-induced cell volume decrease was mimicked by 8-Br-cGMP and abolished by the sGC inhibitor ODQ, the PKG inhibitor (RP)-8-Br-PET-cGMP-S, and the BK(Ca) channel inhibitor IBTX. The BAY-58-2667-induced cell volume decrease was mimicked by 8-Br-cGMP and was abolished by the PKG inhibitor and the BK(Ca) channel inhibitor. Unlike the YC-1 response, ODQ potentiated the BAY-58-2667-induced decreases in cell volume. These data suggest that the NO-independent decrease in TM cell volume is mediated by the sGC/cGMP/PKG pathway and involves K(+) efflux.

Decreased Central Nervous System Grey Matter Volume (GMV) in Smokers Affects Cognitive Abilities: A Systematic Review.

PubMed

Vňuková, Martina; Ptáček, Radek; Raboch, Jiří; Stefano, George B

2017-04-20

Although cigarette smoking is a leading cause of preventable mortality, tobacco is consumed by approximately 22% of the adult population worldwide. Smoking is also a risk factor for cardiovascular disease, affects brain processing, and is a recognized risk factor for Alzheimer disease (AD). Tobacco toxins (e.g., nicotine at high levels) inhaled in smoke may cause disorders resulting in preclinical brain changes. Researchers suggest that there are differences in brain volume between smokers and non-smokers. This review examines these differences in brain grey matter volume (GMV). In March/April 2015, MedLine, Embase, and PsycINFO were searched using the terms: "grey matter" AND "voxel-based" AND "smoking" AND "cigarette". The 4 studies analyzed found brain GMV decreases in smokers compared to non-smokers. Furthermore, sex-specific differences were found; while the thalamus and cerebellum were affected in both sexes, decreased GMV in the olfactory gyrus was found only in male smokers. Age-group differences were also found, and these may suggest pre-existing abnormalities that lead to nicotine dependence in younger individuals. Only 1 study found a positive correlation between number of pack-years smoked and GMV. Smoking decreases GMV in most brain areas. This decrease may be responsible for the cognitive impairment and difficulties with emotional regulation found in smokers compared with non-smokers.

Decreased Central Nervous System Grey Matter Volume (GMV) in Smokers Affects Cognitive Abilities: A Systematic Review

PubMed Central

Vňuková, Martina; Ptáček, Radek; Raboch, Jiří; Stefano, George B.

2017-01-01

Although cigarette smoking is a leading cause of preventable mortality, tobacco is consumed by approximately 22% of the adult population worldwide. Smoking is also a risk factor for cardiovascular disease, affects brain processing, and is a recognized risk factor for Alzheimer disease (AD). Tobacco toxins (e.g., nicotine at high levels) inhaled in smoke may cause disorders resulting in preclinical brain changes. Researchers suggest that there are differences in brain volume between smokers and non-smokers. This review examines these differences in brain grey matter volume (GMV). In March/April 2015, MedLine, Embase, and PsycINFO were searched using the terms: “grey matter” AND “voxel-based” AND “smoking” AND “cigarette”. The 4 studies analyzed found brain GMV decreases in smokers compared to non-smokers. Furthermore, sex-specific differences were found; while the thalamus and cerebellum were affected in both sexes, decreased GMV in the olfactory gyrus was found only in male smokers. Age-group differences were also found, and these may suggest pre-existing abnormalities that lead to nicotine dependence in younger individuals. Only 1 study found a positive correlation between number of pack-years smoked and GMV. Smoking decreases GMV in most brain areas. This decrease may be responsible for the cognitive impairment and difficulties with emotional regulation found in smokers compared with non-smokers. PMID:28426638

Twinning and martensite in a 304 austenitic stainless steel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shen, Yongfeng; Li, Xi; Sun, Xin

2012-08-30

The microstructure characteristics and deformation behavior of 304L stainless steel during tensile deformation at two different strain rates have been investigated by means of interrupted tensile tests, electron-backscatter-diffraction (EBSD) and transmission electron microscopy (TEM) techniques. The volume fractions of transformed martensite and deformation twins at different stages of the deformation process were measured using X-ray diffraction method and TEM observations. It is found that the volume fraction of martensite monotonically increases with increasing strain but decreases with increasing strain rate. On the other hand, the volume fraction of twins increases with increasing strain for strain level less than 57%. Beyondmore » that, the volume fraction of twins decreases with increasing strain. Careful TEM observations show that stacking faults (SFs) and twins preferentially occur before the nucleation of martensite. Meanwhile, both {var_epsilon}-martensite and {alpha}{prime}-martensite are observed in the deformation microstructures, indicating the co-existence of stress induced- transformation and strain-induced-transformation. We also discussed the effects of twinning and martensite transformation on work-hardening as well as the relationship between stacking faults, twinning and martensite transformation.« less

Effects of processing moisture on the physical properties and in vitro digestibility of starch and protein in extruded brown rice and pinto bean composite flours.

PubMed

Sumargo, Franklin; Gulati, Paridhi; Weier, Steven A; Clarke, Jennifer; Rose, Devin J

2016-11-15

The influence of pinto bean flour and processing moisture on the physical properties and in vitro digestibility of rice-bean extrudates has been investigated. Brown rice: pinto bean flour (0%, 15%, 30%, and 45% bean flour) were extruded under 5 moisture conditions (17.2%, 18.1%, 18.3%, 19.5%, and 20.1%). Physical properties [bulk density, unit density, radial expansion, axial expansion, overall expansion, specific volume, hardness, color, water solubility index, and water absorption index] and in vitro starch and protein digestibilities were determined. Increasing bean flour and processing moisture increased density and hardness while decreasing expansion. Rapidly digestible starch decreased and resistant starch increased as bean substitution and processing moisture increased. In vitro protein digestibility increased with increasing bean flour or with decreasing processing moisture. Incorporating bean flour into extruded snacks can negatively affect physical attributes (hardness, density, and expansion) while positively affecting in vitro starch (decrease) and protein (increase) digestibilities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Improving conversion yield of fermentable sugars into fuel ethanol in 1st generation yeast-based production processes.

PubMed

Gombert, Andreas K; van Maris, Antonius J A

2015-06-01

Current fuel ethanol production using yeasts and starch or sucrose-based feedstocks is referred to as 1st generation (1G) ethanol production. These processes are characterized by the high contribution of sugar prices to the final production costs, by high production volumes, and by low profit margins. In this context, small improvements in the ethanol yield on sugars have a large impact on process economy. Three types of strategies used to achieve this goal are discussed: engineering free-energy conservation, engineering redox-metabolism, and decreasing sugar losses in the process. Whereas the two former strategies lead to decreased biomass and/or glycerol formation, the latter requires increased process and/or yeast robustness. Copyright © 2014 Elsevier Ltd. All rights reserved.

Application of steel slag coated with sodium hydroxide to enhance precipitation-coagulation for phosphorus removal.

PubMed

Park, Taejun; Ampunan, Vanvimol; Maeng, Sungkyu; Chung, Eunhyea

2017-01-01

Phosphorus removal has been studied for decades to reduce the environmental impact of phosphorus in natural waterbodies. Slag has been applied for the phosphorus removal by several mechanisms. In this study, sodium hydroxide coating was applied on the slag surface to enhance the efficiency of precipitation-coagulation process. In the batch test, it was found that the capacity of the slag to maintain high pH decreases with increasing its exposure time to the aqueous solution. In the column test, the coarse-grained coated slag showed higher phosphorus removal efficiency than the fine-grained uncoated slag. The coated slag maintained pH higher than uncoated slag and, accordingly, the removal efficiency of phosphorus was higher. Especially, when pH was less than 8, the removal efficiency decreased significantly. However, coated slag provided an excess amount of aluminum and sodium. Thus, a return process to reuse aluminum and sodium as a coagulant was introduced. The return process yields longer lifespan of slag with higher phosphorus removal and lower concentration of cations in the effluent. With the return process, the phosphorus removal efficiency was kept higher than 60% until 150 bed volumes; meanwhile, the efficiency without return process became lower than 60% at 25 bed volumes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Micro-Mechanical Analysis About Kink Band in Carbon Fiber/Epoxy Composites Under Longitudinal Compression

NASA Astrophysics Data System (ADS)

Zhang, Mi; Guan, Zhidong; Wang, Xiaodong; Du, Shanyi

2017-10-01

Kink band is a typical phenomenon for composites under longitudinal compression. In this paper, theoretical analysis and finite element simulation were conducted to analyze kink angle as well as compressive strength of composites. Kink angle was considered to be an important character throughout longitudinal compression process. Three factors including plastic matrix, initial fiber misalignment and rotation due to loading were considered for theoretical analysis. Besides, the relationship between kink angle and fiber volume fraction was improved and optimized by theoretical derivation. In addition, finite element models considering fiber stochastic strength and Drucker-Prager constitutive model for matrix were conducted in ABAQUS to analyze kink band formation process, which corresponded with the experimental results. Through simulation, the loading and failure procedure can be evidently divided into three stages: elastic stage, softening stage, and fiber break stage. It also shows that kink band is a result of fiber misalignment and plastic matrix. Different values of initial fiber misalignment angle, wavelength and fiber volume fraction were considered to explore the effects on compressive strength and kink angle. Results show that compressive strength increases with the decreasing of initial fiber misalignment angle, the decreasing of initial fiber misalignment wavelength and the increasing of fiber volume fraction, while kink angle decreases in these situations. Orthogonal array in statistics was also built to distinguish the effect degree of these factors. It indicates that initial fiber misalignment angle has the largest impact on compressive strength and kink angle.

Emergency department spirometric volume and base deficit delineate risk for torso injury in stable patients

PubMed Central

Dunham, C Michael; Sipe, Eilynn K; Peluso, LeeAnn

2004-01-01

Background We sought to determine torso injury rates and sensitivities associated with fluid-positive abdominal ultrasound, metabolic acidosis (increased base deficit and lactate), and impaired pulmonary physiology (decreased spirometric volume and PaO2/FiO2). Methods Level I trauma center prospective pilot and post-pilot study (2000–2001) of stable patients. Increased base deficit was < 0.0 in ethanol-negative and ≤ -3.0 in ethanol-positive patients. Increased lactate was > 2.5 mmol/L in ethanol-negative and ≥ 3.0 mmol/L in ethanol-positive patients. Decreased PaO2/FiO2 was < 350 and decreased spirometric volume was < 1.8 L. Results Of 215 patients, 66 (30.7%) had a torso injury (abdominal/pelvic injury n = 35 and/or thoracic injury n = 43). Glasgow Coma Scale score was 14.8 ± 0.5 (13–15). Torso injury rates and sensitivities were: abdominal ultrasound negative and normal base deficit, lactate, PaO2/FiO2, and spirometric volume – 0.0% & 0.0%; normal base deficit and normal spirometric volume – 4.2% & 4.5%; chest/abdominal soft tissue injury – 37.8% & 47.0%; increased lactate – 39.7% & 47.0%; increased base deficit – 41.3% & 75.8%; increased base deficit and/or decreased spirometric volume – 43.8% & 95.5%; decreased PaO2/FiO2 – 48.9% & 33.3%; positive abdominal ultrasound – 62.5% & 7.6%; decreased spirometric volume – 73.4% & 71.2%; increased base deficit and decreased spirometric volume – 82.9% & 51.5%. Conclusions Trauma patients with normal base deficit and spirometric volume are unlikely to have a torso injury. Patients with increased base deficit or lactate, decreased spirometric volume, decreased PaO2/FiO2, or positive FAST have substantial risk for torso injury. Increased base deficit and/or decreased spirometric volume are highly sensitive for torso injury. Base deficit and spirometric volume values are readily available and increase or decrease the suspicion for torso injury. PMID:14731306

Automated processing of whole blood samples into microliter aliquots of plasma.

PubMed

Burtis, C A; Johnson, W W; Walker, W A

1988-01-01

A rotor that accepts and automatically processes a bulk aliquot of a single blood sample into multiple aliquots of plasma has been designed and built. The rotor consists of a central processing unit, which includes a disk containing eight precision-bore capillaries. By varying the internal diameters of the capillaries, aliquot volumes ranging 1 to 10 mul can be prepared. In practice, an unmeasured volume of blood is placed in a centre well, and, as the rotor begins to spin, is moved radially into a central annular ring where it is distributed into a series of processing chambers. The rotor is then spun at 3000 rpm for 10 min. When the centrifugal field is removed by slowly decreasing the rotor speed, an aliquot of plasma is withdrawn by capillary action into each of the capillary tubes. The disk containing the eight measured aliquots of plasma is subsequently removed and placed in a modifed rotor for conventional centrifugal analysis. Initial evaluation of the new rotor indicates that it is capable of producing discrete, microliter volumes of plasma with a degree of accuracy and precision approaching that of mechanical pipettes.

Effect of Cooling Mode on Microstructure and Mechanical Properties of Pipeline Steel for Strain Based Design and Research on its Deformation Mechanism

NASA Astrophysics Data System (ADS)

Hesong, Zhang; Yonglin, Kang

With the rapid development of oil and gas industry long distance pipelines inevitably pass through regions with complex geological activities. In order to avoid large deformation the pipelines must be designed based on strain criteria. In this paper the alloy system of X80 high deformability pipeline steel was designed which was 0.25%Mo-0.05%C-1.75%Mn. The effect of controlled cooling process on microstructure and mechanical properties of X80 high deformability pipeline steel were systematically investigated. Through the two-stage controlled cooling process the microstructure of the X80 high deformability pipeline steel were ferrite, bainite and M/A island. There were two kinds of ferrite which were polygonal ferrite (PF) and quasi-polygonal ferrite (QF). The bainite was granular bainite ferrite (GF). Along with the decrease of the start cooling temperature, the volume fraction of ferrite and M/A both increased, the yield ratio (Y/T) decreased, the uniform elongation (uEl) increased firstly with the content of ferrite increased but then decreased with the content and size of M/A increased. When the finish cooling temperature decreasing, the size of M/A became finer. As the start cooling temperature was 690 °C and the finish cooling temperature was 450 °C the volume fraction of ferrite was 23%, the size of ferrite grain was 5μm, the size of M/A island was below 1μm and the structure uniformity was the best. The deformation mechanism of X80 high deformability pipeline steel was analyzed. The best way to improve the work hardening rate was reducing the size of M/A islands on the premise of a certain volume fraction. The decreasing path of instantaneous strain hardening index (n*-value) showed three stages in the deformation process. The n*-value kept stable in the second stage, the reason was that the retained austenite transformed into martensite and the phase transition improved the strain hardening ability of the microstructure. This phenomenon was called transformation induced plasticity effect (TRIP).

Lung Function before and Two Days after Open-Heart Surgery.

PubMed

Urell, Charlotte; Westerdahl, Elisabeth; Hedenström, Hans; Janson, Christer; Emtner, Margareta

2012-01-01

Reduced lung volumes and atelectasis are common after open-heart surgery, and pronounced restrictive lung volume impairment has been found. The aim of this study was to investigate factors influencing lung volumes on the second postoperative day. Open-heart surgery patients (n = 107, 68 yrs, 80% male) performed spirometry both before surgery and on the second postoperative day. The factors influencing postoperative lung volumes and decrease in lung volumes were investigated with univariate and multivariate analyses. Associations between pain (measured by numeric rating scale) and decrease in postoperative lung volumes were calculated with Spearman rank correlation test. Lung volumes decreased by 50% and were less than 40% of the predictive values postoperatively. Patients with BMI >25 had lower postoperative inspiratory capacity (IC) (33 ± 14% pred.) than normal-weight patients (39 ± 15% pred.), (P = 0.04). More pain during mobilisation was associated with higher decreases in postoperative lung volumes (VC: r = 0.33, P = 0.001; FEV(1): r = 0.35, P ≤ 0.0001; IC: r = 0.25, P = 0.01). Patients with high BMI are a risk group for decreased postoperative lung volumes and should therefore receive extra attention during postoperative care. As pain is related to a larger decrease in postoperative lung volumes, optimal pain relief for the patients should be identified.

Lung Function before and Two Days after Open-Heart Surgery

PubMed Central

Urell, Charlotte; Westerdahl, Elisabeth; Hedenström, Hans; Janson, Christer; Emtner, Margareta

2012-01-01

Reduced lung volumes and atelectasis are common after open-heart surgery, and pronounced restrictive lung volume impairment has been found. The aim of this study was to investigate factors influencing lung volumes on the second postoperative day. Open-heart surgery patients (n = 107, 68 yrs, 80% male) performed spirometry both before surgery and on the second postoperative day. The factors influencing postoperative lung volumes and decrease in lung volumes were investigated with univariate and multivariate analyses. Associations between pain (measured by numeric rating scale) and decrease in postoperative lung volumes were calculated with Spearman rank correlation test. Lung volumes decreased by 50% and were less than 40% of the predictive values postoperatively. Patients with BMI >25 had lower postoperative inspiratory capacity (IC) (33 ± 14% pred.) than normal-weight patients (39 ± 15% pred.), (P = 0.04). More pain during mobilisation was associated with higher decreases in postoperative lung volumes (VC: r = 0.33, P = 0.001; FEV1: r = 0.35, P ≤ 0.0001; IC: r = 0.25, P = 0.01). Patients with high BMI are a risk group for decreased postoperative lung volumes and should therefore receive extra attention during postoperative care. As pain is related to a larger decrease in postoperative lung volumes, optimal pain relief for the patients should be identified. PMID:22924127

A mechanism of adaptation to hypergravity in the statocyst of Aplysia californica

NASA Technical Reports Server (NTRS)

Pedrozo, H. A.; Schwartz, Z.; Luther, M.; Dean, D. D.; Boyan, B. D.; Wiederhold, M. L.

1996-01-01

The gravity-sensing organ of Aplysia californica consists of bilaterally paired statocysts containing statoconia, which are granules composed of calcium carbonate crystals in an organic matrix. In early embryonic development, Aplysia contain a single granule called a statolith, and as the animal matures, statoconia production takes place. The objective of this study was to determine the effect of hypergravity on statoconia production and homeostasis and explore a possible physiologic mechanism for regulating this process. Embryonic Aplysia were exposed to normogravity or 3 x g or 5.7 x g and each day samples were analyzed for changes in statocyst, statolith, and body dimensions until they hatched. In addition, early metamorphosed Aplysia (developmental stages 7-10) were exposed to hypergravity (2 x g) for 3 weeks, and statoconia number and statocyst and statoconia volumes were determined. We also determined the effects of hypergravity on statoconia production and homeostasis in statocysts isolated from developmental stage 10 Aplysia. Since prior studies demonstrated that urease was important in the regulation of statocyst pH and statoconia formation, we also evaluated the effect of hypergravity on urease activity. The results show that hypergravity decreased statolith and body diameter in embryonic Aplysia in a magnitude-dependent fashion. In early metamorphosed Aplysia, hypergravity decreased statoconia number and volume. Similarly, there was an inhibition of statoconia production and a decrease in statoconia volume in isolated statocysts exposed to hypergravity in culture. Urease activity in statocysts decreased after exposure to hypergravity and was correlated with the decrease in statoconia production observed. In short, there was a decrease in statoconia production with exposure to hypergravity both in vivo and in vitro and a decrease in urease activity. It is concluded that exposure to hypergravity downregulates urease activity, resulting in a significant decrease in the formation of statoconia.

Linking dynamics of transport timescale and variations of hypoxia in the Chesapeake Bay

NASA Astrophysics Data System (ADS)

Hong, Bo; Shen, Jian

2013-11-01

Dissolved oxygen (DO) replenishment in the bottom waters of an estuary depends on physical processes that are significantly influenced by external forcings. The vertical exchange time (VET) is introduced in this study to quantify the physical processes that regulate the DO replenishment in the Chesapeake Bay. A 3-D numerical model was applied to simulate the circulation, VET, and DO. Results indicate that VET is a suitable parameter for evaluating the bottom DO condition over both seasonal and interannual timescales. The VET is negatively correlated with the bottom DO. Hypoxia (DO <2 mg L-1) will develop in the Bay when VET is greater than 23 days in summer if mean total DO consumption rate is about 0.3 g O2 m-3 d-1. This critical VET value may vary around 23 days when the total DO consumption rate changes. The VET volume (volume of water mass with VET >23 days) can account for 77% of variations of hypoxic volume in the main Bay. The VET cannot explain all the DO variations as it can only account for the contribution of physical processes that regulate DO replenishment. It is found that the short-term vertical exchange process is highly controlled by the wind forcing. The VET volume decreases when the high-speed wind events are frequent. The summertime VET volume is less sensitive to short-term variations (pulses) of river discharge. It is sensitive to the total amount of river discharge and the high VET volume can be expected in the wet year.

[Course of ejection fraction, regurgitation fraction and ventricular volumes during exertion in chronic aortic insufficiency. Study using technetium 99m gamma-cineangiography].

PubMed

Bassand, J P; Faivre, R; Berthout, P; Cardot, J C; Verdenet, J; Bidet, R; Maurat, J P

1985-06-01

Previous studies have shown that variations of the ejection fraction (EF) during exercise were representative of the contractile state of the left ventricle: an increased EF on effort is considered to be physiological, whilst a decrease would indicate latent LV dysfunction unmasked during exercise. This hypothesis was tested by performing Technetium 99 gamma cineangiography at equilibrium under basal conditions and at maximal effort in 8 healthy subjects and 44 patients with pure, severe aortic regurgitation to measure the ejection and regurgitant fractions and the variations in end systolic and end diastolic LV volume. In the control group the EF increased and end systolic volume decreased significantly on effort whilst the regurgitant fraction and end diastolic volume were unchanged. In the 44 patients with aortic regurgitation no significant variations in EF, end systolic and end diastolic volumes were observed because the individual values were very dispersed. Variations of the EF and end systolic volume were inversely correlated. The regurgitant fraction decreased significantly on effort. Based on the variations of the EF and end systolic volume three different types of response to effort could be identified: in 7 patients, the EF increased on effort and end systolic volume decreased without any significant variation in the end diastolic volume, as in the group of normal control subjects; in 22 patients, a reduction in EF was observed on effort, associated with an increased end systolic volume. These changes indicated latent IV dysfunction inapparent at rest and unmasked by exercise; in a third group of 15 patients, the EF decreased on effort despite a physiological decrease in end systolic volume due to a greater decrease in end diastolic volume.(ABSTRACT TRUNCATED AT 250 WORDS)

Disposition of pentachlorophenol in rainbow trout (Salmo gairdneri ): Effect of inhibition of metabolism

USGS Publications Warehouse

Stehly, G.R.; Hayton, W.L.

1989-01-01

The accumulation kinetics of pentachlorophenol (PCP) were investigated in rainbow trout (Salmo gairdneri ) in the absence and presence of 25 mg/l salicylamide, an inhibitor of PCP metabolism. After exposure to 5 mu g/l PCP over 1-96 h, the amount of PCP in the whole fish, its concentration in water and the total amount of metabolites (water, whole fish and bile) were measured. Equations for these variables, based on a two compartment pharmacokinetic model, were fitted simultaneously to the data using the computer program NONLIN, which uses an iterative nonlinear least squares technique. Salicylamide decreased the metabolic clearance of PCP, which resulted in an increase in the bioconcentration factor (BCF); this increase was partially offset by a salicylamide-induced decrease in the apparent volume of distribution of PCP. A clearance-volume compartment model permitted partitioning of the BCF in terms of the underlying physiologic and biochemical processes (uptake clearance, metabolic clearance and apparent volume of distribution).

Destruction of newly released red blood cells in space flight

NASA Technical Reports Server (NTRS)

Alfrey, C. P.; Udden, M. M.; Huntoon, C. L.; Driscoll, T.

1996-01-01

Space flight results in a rapid change in total blood volume, plasma volume, and red blood cell mass because the space to contain blood is decreased. The plasma volume and total blood volume decreases during the first hours in space and remain at a decreased level for the remainder of the flight. During the first several hours following return to earth, plasma volume and total blood volume increase to preflight levels. During the first few days in space recently produced red blood cells disappear from the blood resulting in a decrease in red blood cell mass of 10-15%. Red cells 12 d old or older survive normally and production of new cells continues at near preflight levels. After the first few days in space, the red cell mass is stable at the decreased level. Following return to earth the hemoglobin and red blood cell mass concentrations decrease reflecting the increase in plasma volume. The erythropoietin levels increase responding to "postflight anemia"; red cell production increases, and the red cell mass is restored to preflight levels after several weeks.

Processing, structure, and characterizaton of nickel-alumina composites obtained by the partial reduction of zirconia-doped nickel-aluminum oxide and application to the tempering of ceramics

NASA Astrophysics Data System (ADS)

Barbieri, Thomas John

1999-11-01

Partial reduction of the spinel compound NiAl2O4 results in a two phase composite mixture of Ni + Al2O3. The reduction reaction has a volume decrease associated with it, which theoretically could generate large residual stresses, which have the potential to "temper" a ceramic, i.e. to place the surface of a ceramic component into a state of residual compression. As the first step towards tempering a ceramic, it is necessary to demonstrate that appreciable stresses can be generated by this volume change, since they may be relieved by either cracking or diffusional relaxation processes at the high temperature of the reduction reaction. It was necessary to determine the best processing methods to use for producing the tempered specimens. Results are presented from a systematic study on the effect of the variation of processing parameters on the reduction behavior of NiAl2O4 doped with ZrO2. Specimen characteristics of interest were time required for reduction, microstructural development, volume contraction achieved and porosity generated during reduction, and the ability to survive the reduction process without fracturing. These results were applied to the tempering process. A simple specimen geometry was used for tempering which involved an Al 2O3 cylinder bonded to an outer NiAl2O4 ring. Finite element calculations were performed to predict the residual stresses generated by the volume contraction of the ring and the coefficient of thermal expansion, (CTE) mismatch between the Al2O3 core and the reduced composite ring. Stress measurements performed on the Al2 O3 core of each specimen using the "d vs. Sin 2Psi" method of X-ray diffraction indicate that only the CTE-induced stresses remain in the specimens after completion of the tempering process. Microstructural analysis of the tempered specimens was performed to determine if residual stresses were developed during reduction, and what processes occurred to relieve these stresses. The results indicate that stresses are generated during the reduction process, but they are dissipated through catastrophic fracture, cation rearrangement in the lattice, and creep. Further evidence of the presence of residual stresses during reduction was found in a decrease in coarsening rate in tempered specimens.

On the effect of hydrostatic pressure on the conformational stability of globular proteins.

PubMed

Graziano, Giuseppe

2015-12-01

The model developed for cold denaturation (Graziano, PCCP 2010, 12, 14245-14252) is extended to rationalize the dependence of protein conformational stability upon hydrostatic pressure, at room temperature. A pressure- volume work is associated with the process of cavity creation for the need to enlarge the liquid volume against hydrostatic pressure. This contribution destabilizes the native state that has a molecular volume slightly larger than the denatured state due to voids existing in the protein core. Therefore, there is a hydrostatic pressure value at which the pressure-volume contribution plus the conformational entropy loss of the polypeptide chain are able to overwhelm the stabilizing gain in translational entropy of water molecules, due to the decrease in water accessible surface area upon folding, causing denaturation. © 2015 Wiley Periodicals, Inc.

Decreased Cognitive Functioning After Electroconvulsive Therapy Is Related to Increased Hippocampal Volume: Exploring the Role of Brain Plasticity.

PubMed

van Oostrom, Iris; van Eijndhoven, Philip; Butterbrod, Elke; van Beek, Maria H; Janzing, Joost; Donders, Rogier; Schene, Aart; Tendolkar, Indira

2018-06-01

Electroconvulsive therapy (ECT) is still the most effective treatment of severe and therapy-refractory major depressive disorder. Cognitive side effects are the major disadvantage of ECT. Cognitive deficits are generally temporary in nature and may be mediated by the hippocampus. Recent studies have shown a temporary increase in hippocampal volume and a temporary decrease in cognitive functioning post-ECT compared with pre-ECT. This study investigates whether these volumetric changes are related to changes in cognitive functioning after ECT. Nineteen medication-free patients with treatment-resistant major depressive disorder underwent a whole-brain magnetic resonance imaging scan and a neuropsychological examination (including the Rey auditory verbal learning task, Wechsler Memory Scale Visual Reproduction, fluency, Trail Making Task) within 1 week before and within 1 week after the course of ECT. Electroconvulsive therapy was administered twice a week bitemporally with a brief pulse. A matched healthy control group (n = 18) received the same neuropsychological examination and at a similar interval to that of the patients. Hippocampal volumes increased significantly from pretreatment to posttreatment in patients. Mean performance on cognitive tasks declined, or remained stable, whereas performance in controls generally improved because of retesting effects. The increase in hippocampal volume was related to changes in cognitive performance, indicating that this increase co-occurred with a decrease in cognitive functioning. Our findings tentatively suggest that the temporal increase in hippocampal volume after treatment, which may result from neurotrophic processes and is thought to be crucial for the antidepressive effect, is also related to the temporary cognitive side effects of ECT.

Data Summarization in the Node by Parameters (DSNP): Local Data Fusion in an IoT Environment.

PubMed

Maschi, Luis F C; Pinto, Alex S R; Meneguette, Rodolfo I; Baldassin, Alexandro

2018-03-07

With the advent of the Internet of Things, billions of objects or devices are inserted into the global computer network, generating and processing data at a volume never imagined before. This paper proposes a way to collect and process local data through a data fusion technology called summarization. The main feature of the proposal is the local data fusion, through parameters provided by the application, ensuring the quality of data collected by the sensor node. In the evaluation, the sensor node was compared when performing the data summary with another that performed a continuous recording of the collected data. Two sets of nodes were created, one with a sensor node that analyzed the luminosity of the room, which in this case obtained a reduction of 97% in the volume of data generated, and another set that analyzed the temperature of the room, obtaining a reduction of 80% in the data volume. Through these tests, it has been proven that the local data fusion at the node can be used to reduce the volume of data generated, consequently decreasing the volume of messages generated by IoT environments.

Looking into the crystal ball: future device learning using hybrid e-beam and optical lithography (Keynote Paper)

NASA Astrophysics Data System (ADS)

Steen, S. E.; McNab, S. J.; Sekaric, L.; Babich, I.; Patel, J.; Bucchignano, J.; Rooks, M.; Fried, D. M.; Topol, A. W.; Brancaccio, J. R.; Yu, R.; Hergenrother, J. M.; Doyle, J. P.; Nunes, R.; Viswanathan, R. G.; Purushothaman, S.; Rothwell, M. B.

2005-05-01

Semiconductor process development teams are faced with increasing process and integration complexity while the time between lithographic capability and volume production has remained more or less constant over the last decade. Lithography tools have often gated the volume checkpoint of a new device node on the ITRS roadmap. The processes have to be redeveloped after the tooling capability for the new groundrule is obtained since straight scaling is no longer sufficient. In certain cases the time window that the process development teams have is actually decreasing. In the extreme, some forecasts are showing that by the time the 45nm technology node is scheduled for volume production, the tooling vendors will just begin shipping the tools required for this technology node. To address this time pressure, IBM has implemented a hybrid-lithography strategy that marries the advantages of optical lithography (high throughput) with electron beam direct write lithography (high resolution and alignment capability). This hybrid-lithography scheme allows for the timely development of semiconductor processes for the 32nm node, and beyond. In this paper we will describe how hybrid lithography has enabled early process integration and device learning and how IBM applied e-beam & optical hybrid lithography to create the world's smallest working SRAM cell.

Effects of valerian consumption during pregnancy on cortical volume and the levels of zinc and copper in the brain tissue of mouse fetus.

PubMed

Mahmoudian, Alireza; Rajaei, Ziba; Haghir, Hossein; Banihashemian, Shahaboldin; Hami, Javad

2012-04-01

The aim of the present study was to determine the effects of valerian (Valeriana officinalis) consumption in pregnancy on cortical volume and the levels of zinc and copper, two essential elements that affect brain development and function, in the brain tissues of mouse fetuses. Pregnant female mice were treated with either saline or 1.2 g/kg body weight valerian extract intraperitoneally daily on gestation days (GD) 7 to 17. On GD 20, mice were sacrificed and their fetuses were collected. Fetal brains were dissected, weighed and processed for histological analysis. The volume of cerebral cortex was estimated by the Cavalieri principle. The levels of zinc and copper in the brain tissues were measured by atomic absorption spectroscopy. The results indicated that valerian consumption in pregnancy had no significant effect on brain weight, cerebral cortex volume and copper level in fetal brain. However,it significantly decreased the level of zinc in the brain (P<0.05). Using valerian during midgestation do not have an adverse effect on cerebral cortex; however,it caused a significant decrease in zinc level in the fetal brain. This suggests that valerian use should be limited during pregnancy.

[Evaluation of salivary gland function in women with autoimmune thyroid diseases].

PubMed

Koczor-Rozmus, Aleksandra; Zwirska-Korczala, Krystyna; Sadlak-Nowicka, Jadwiga; Ilewicz, Leşzek; Mayer-Parka, Danuta; Wierucka-Młynarczyk, Beata

2003-01-01

The function of the salivary glands is regulated by nervous system which influences salivary circulation. Moreover the volume of secreted saliva depends on the humoral agents, including thyroid hormones. The aim of the study was to determine the quantity of the secreted mixed resting and stimulated saliva in women with autoimmune thyroid diseases (AITD) depending on the function of the thyroid gland (hyperthyroidism, hypothyroidism and euthyroidism). The association between thyroid antibody concentrations (TPO-Ab, Tg-Ab, TR-Ab) and volume of secreted saliva was also examined. Studies were performed in 106 women suffering from AITD and 15 healthy volunteers. In hyperthyroid women there was a decrease in volumes of resting (57.14%) and stimulated (89.29%) saliva. Similarly, a decrease in secretion of resting (75%) and stimulated (66.67%) saliva was shown in hypothyroid women. In euthyroid patients with AITD there was a partial normalisation of salivary glands function. The negative correlation between concentrations of TPO-Ab, Tg-Ab and the volume of resting and stimulated saliva was found. In conclusion, AITD may be associated with disturbances in salivary secretion which depends on thyroid hormones production. It can be suggested that autoimmunological processes within salivary glands may influence their function.

Gray and white matter volume abnormalities in monozygotic and same-gender dizygotic twins discordant for schizophrenia.

PubMed

Hulshoff Pol, Hilleke E; Brans, Rachel G H; van Haren, Neeltje E M; Schnack, Hugo G; Langen, Marieke; Baaré, Wim F C; van Oel, Clarine J; Kahn, René S

2004-01-15

Whole brain tissue volume decreases in schizophrenia have been related to both genetic risk factors and disease-related (possibly nongenetic) factors; however, whether genetic and environmental risk factors in the brains of patients with schizophrenia are differentially reflected in gray or white matter volume change is not known. Magnetic resonance imaging (1.5 T) brain scans of 11 monozygotic and 11 same-gender dizygotic twin pairs discordant for schizophrenia were acquired and compared with 11 monozygotic and 11 same-gender dizygotic healthy control twin pairs. Repeated-measures volume analysis of covariance revealed decreased whole brain volume in the patients with schizophrenia as compared with their co-twins and with healthy twin pairs. Decreased white matter volume was found in discordant twin pairs compared with healthy twin pairs, particularly in the monozygotic twin pairs. A decrease in gray matter was found in the patients compared with their co-twins and compared with the healthy twins. The results suggest that the decreases in white matter volume reflect the increased genetic risk to develop schizophrenia, whereas the decreases in gray matter volume are related to environmental risk factors. Study of genes involved in the (maintenance) of white matter structures may be particularly fruitful in schizophrenia.

Can prostatic arterial embolisation (PAE) reduce the volume of the peripheral zone? MRI evaluation of zonal anatomy and infarction after PAE.

PubMed

Lin, Yen-Ting; Amouyal, Grégory; Correas, Jean-Michel; Pereira, Héléna; Pellerin, Olivier; Del Giudice, Costantino; Déan, Carole; Thiounn, Nicolas; Sapoval, Marc

2016-10-01

To assess the impact of prostatic arterial embolisation (PAE) on various prostate gland anatomical zones. We retrospectively reviewed paired MRI scans obtained before and after PAE for 25 patients and evaluated changes in volumes of the median lobe (ML), central gland (CG), peripheral zone (PZ) and whole prostate gland (WPV) following PAE. We used manual segmentation to calculate volume on axial view T2-weighted images for ML, CG and WPV. We calculated PZ volume by subtracting CG volume from WPV. Enhanced phase on dynamic contrasted-enhanced MRI was used to evaluate the infarction areas after PAE. Clinical results of International Prostate Symptom Score and International Index of Erectile Function questionnaires and the urodynamic study were evaluated before and after PAE. Significant reductions in volume were observed after PAE for ML (26.2 % decrease), CG (18.8 %), PZ (16.4 %) and WPV (19.1 %; p < 0.001 for all these volumes). Patients with clinical failure had smaller volume reductions for WPV, ML and CG (all p < 0.05). Patients with significant CG infarction after PAE displayed larger WPV, ML and CG volume reductions (all p < 0.01). PAE can significantly decrease WPV, ML, CG and PZ volumes, and poor clinical outcomes are associated with smaller volume reductions. • The MRI segmentation method provides detailed comparisons of prostate volume change. • Prostatic arterial embolisation (PAE) decreased central gland and peripheral zone volumes. • Prostates with infarction after PAE showed larger decreases in volume. • A larger decrease in prostate volume is associated with clinical success.

White Matter Atrophy and Cognitive Dysfunctions in Neuromyelitis Optica

PubMed Central

Blanc, Frederic; Noblet, Vincent; Jung, Barbara; Rousseau, François; Renard, Felix; Bourre, Bertrand; Longato, Nadine; Cremel, Nadjette; Di Bitonto, Laure; Kleitz, Catherine; Collongues, Nicolas; Foucher, Jack; Kremer, Stephane; Armspach, Jean-Paul; de Seze, Jerome

2012-01-01

Neuromyelitis optica (NMO) is an inflammatory disease of central nervous system characterized by optic neuritis and longitudinally extensive acute transverse myelitis. NMO patients have cognitive dysfunctions but other clinical symptoms of brain origin are rare. In the present study, we aimed to investigate cognitive functions and brain volume in NMO. The study population consisted of 28 patients with NMO and 28 healthy control subjects matched for age, sex and educational level. We applied a French translation of the Brief Repeatable Battery (BRB-N) to the NMO patients. Using SIENAx for global brain volume (Grey Matter, GM; White Matter, WM; and whole brain) and VBM for focal brain volume (GM and WM), NMO patients and controls were compared. Voxel-level correlations between diminished brain concentration and cognitive performance for each tests were performed. Focal and global brain volume of NMO patients with and without cognitive impairment were also compared. Fifteen NMO patients (54%) had cognitive impairment with memory, executive function, attention and speed of information processing deficits. Global and focal brain atrophy of WM but not Grey Matter (GM) was found in the NMO patients group. The focal WM atrophy included the optic chiasm, pons, cerebellum, the corpus callosum and parts of the frontal, temporal and parietal lobes, including superior longitudinal fascicle. Visual memory, verbal memory, speed of information processing, short-term memory and executive functions were correlated to focal WM volumes. The comparison of patients with, to patients without cognitive impairment showed a clear decrease of global and focal WM, including brainstem, corticospinal tracts, corpus callosum but also superior and inferior longitudinal fascicles. Cognitive impairment in NMO patients is correlated to the decreased of global and focal WM volume of the brain. Further studies are needed to better understand the precise origin of cognitive impairment in NMO patients, particularly in the WM. PMID:22509264

Thermodynamics with pressure and volume under charged particle absorption

NASA Astrophysics Data System (ADS)

Gwak, Bogeun

2017-11-01

We investigate the variation of the charged anti-de Sitter black hole under charged particle absorption by considering thermodynamic volume. When the energy of the particle is considered to contribute to the internal energy of the black hole, the variation exactly corresponds to the prediction of the first law of thermodynamics. Nevertheless, we find the decrease of the Bekenstein-Hawking entropy for extremal and near-extremal black holes under the absorption, which is an irreversible process. This violation of the second law of thermodynamics is only found when considering thermodynamic volume. We test the weak cosmic censorship conjecture affected by the violation. Fortunately, the conjecture is still valid, but extremal and near-extremal black holes do not change their configurations when any particle enters the black hole. This result is quite different from the case in which thermodynamic volume is not considered.

Changes in regional gray matter volume in women with chronic pelvic pain - a voxel based morphometry study

PubMed Central

As-Sanie, Sawsan; Harris, Richard; Napadow, Vitaly; Kim, Jieun; Neshewat, Gina; Kairys, Anson; Williams, David; Clauw, Daniel; Schmidt-Wilcke, Tobias

2012-01-01

Chronic pelvic pain (CPP) is a highly prevalent pain condition, estimated to affect 15-20% of women in the United States. Endometriosis is often associated with CPP, however other factors, such as pre-existing or concomitant changes of the central pain system, might contribute to the development of chronic pain. We applied voxel-based morphometry to determine whether women with CPP with and without endometriosis display changes in brain morphology in regions known to be involved in pain processing.Four subgroups of women participated: 17 with endometriosis and CPP, 15 with endometriosis without CPP, 6 with CPP without endometriosis, as well as 23 healthy controls. All patients with endometriosis and/or CPP were surgically-confirmed. Relative to controls, women with endometriosis-associated CPP displayed decreased gray matter volume in brain regions involved in pain perception including the left thalamus, left cingulategyrus, right putamen, and right insula. Women with CPP without endometriosis also showed decreases in gray matter volume in the left thalamus. Such decreases were not observed in patients with endometriosis that had no CPP. We conclude thatCPP is associated with changes in regional gray matter volume within the central pain system. Although endometriosis may be an important risk factor for the development of CPP, acting as a cyclic source of peripheral nociceptive input, our data support the notion that changes in the central pain system also play an important role in the development of chronic pain, regardless of the presence of endometriosis. PMID:22387096

Neuroanatomical and Neuropsychological Correlates of the Cerebellum in Children with Attention-Deficit/Hyperactivity Disorder-Combined Type

ERIC Educational Resources Information Center

Bledsoe, Jesse C.; Semrud-Clikeman, Margaret; Pliszka, Steven R.

2011-01-01

Objective: Studies of healthy individuals and those with cerebellar damage have implicated the cerebellum in a variety of cognitive and behavioral processes. Decreased cerebellar volume has been found in children with attention-deficit/hyperactivity disorder (ADHD) and differentially related to behavioral outcomes. The present study investigated…

Hydrothermal carbonization (HTC) of wheat straw: influence of feedwater pH prepared by acetic acid and potassium hydroxide.

PubMed

Reza, M Toufiq; Rottler, Erwin; Herklotz, Laureen; Wirth, Benjamin

2015-04-01

In this study, influence of feedwater pH (2-12) was studied for hydrothermal carbonization (HTC) of wheat straw at 200 and 260°C. Acetic acid and KOH were used as acidic and basic medium, respectively. Hydrochars were characterized by elemental and fiber analyses, SEM, surface area, pore volume and size, and ATR-FTIR, while HTC process liquids were analyzed by HPLC and GC. Both hydrochar and HTC process liquid qualities vary with feedwater pH. At acidic pH, cellulose and elemental carbon increase in hydrochar, while hemicellulose and pseudo-lignin decrease. Hydrochars produced at pH 2 feedwater has 2.7 times larger surface area than that produced at pH 12. It also has the largest pore volume (1.1 × 10(-1) ml g(-1)) and pore size (20.2 nm). Organic acids were increasing, while sugars were decreasing in case of basic feedwater, however, phenolic compounds were present only at 260°C and their concentrations were increasing in basic feedwater. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dynamics of chest wall volume regulation during constant work rate exercise in patients with chronic obstructive pulmonary disease

PubMed Central

Takara, L.S.; Cunha, T.M.; Barbosa, P.; Rodrigues, M.K.; Oliveira, M.F.; Nery, L.E.; Neder, J.A.

2012-01-01

This study evaluated the dynamic behavior of total and compartmental chest wall volumes [(VCW) = rib cage (VRC) + abdomen (VAB)] as measured breath-by-breath by optoelectronic plethysmography during constant-load exercise in patients with stable chronic obstructive pulmonary disease. Thirty males (GOLD stages II-III) underwent a cardiopulmonary exercise test to the limit of tolerance (Tlim) at 75% of peak work rate on an electronically braked cycle ergometer. Exercise-induced dynamic hyperinflation was considered to be present when end-expiratory (EE) VCW increased in relation to resting values. There was a noticeable heterogeneity in the patterns of VCW regulation as EEVCW increased non-linearly in 17/30 “hyperinflators” and decreased in 13/30 “non-hyperinflators” (P < 0.05). EEVAB decreased slightly in 8 of the “hyperinflators”, thereby reducing and slowing the rate of increase in end-inspiratory (EI) VCW (P < 0.05). In contrast, decreases in EEVCW in the “non-hyperinflators” were due to the combination of stable EEVRC with marked reductions in EEVAB. These patients showed lower EIVCW and end-exercise dyspnea scores but longer Tlim than their counterparts (P < 0.05). Dyspnea increased and Tlim decreased non-linearly with a faster rate of increase in EIVCW regardless of the presence or absence of dynamic hyperinflation (P < 0.001). However, no significant between-group differences were observed in metabolic, pulmonary gas exchange and cardiovascular responses to exercise. Chest wall volumes are continuously regulated during exercise in order to postpone (or even avoid) their migration to higher operating volumes in patients with COPD, a dynamic process that is strongly dependent on the behavior of the abdominal compartment. PMID:23250012

SU-D-201-07: Exploring the Utility of 4D FDG-PET/CT Scans in Design of Radiation Therapy Planning Compared with 3D PET/CT: A Prospective Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, C; Yin, Y

2015-06-15

Purpose: A method using four-dimensional(4D) PET/CT in design of radiation treatment planning was proposed and the target volume and radiation dose distribution changes relative to standard three-dimensional (3D) PET/CT were examined. Methods: A target deformable registration method was used by which the whole patient’s respiration process was considered and the effect of respiration motion was minimized when designing radiotherapy planning. The gross tumor volume of a non-small-cell lung cancer was contoured on the 4D FDG-PET/CT and 3D PET/CT scans by use of two different techniques: manual contouring by an experienced radiation oncologist using a predetermined protocol; another technique using amore » constant threshold of standardized uptake value (SUV) greater than 2.5. The target volume and radiotherapy dose distribution between VOL3D and VOL4D were analyzed. Results: For all phases, the average automatic and manually GTV volume was 18.61 cm3 (range, 16.39–22.03 cm3) and 31.29 cm3 (range, 30.11–35.55 cm3), respectively. The automatic and manually volume of merged IGTV were 27.82 cm3 and 49.37 cm3, respectively. For the manual contour, compared to 3D plan the mean dose for the left, right, and total lung of 4D plan have an average decrease 21.55%, 15.17% and 15.86%, respectively. The maximum dose of spinal cord has an average decrease 2.35%. For the automatic contour, the mean dose for the left, right, and total lung have an average decrease 23.48%, 16.84% and 17.44%, respectively. The maximum dose of spinal cord has an average decrease 1.68%. Conclusion: In comparison to 3D PET/CT, 4D PET/CT may better define the extent of moving tumors and reduce the contouring tumor volume thereby optimize radiation treatment planning for lung tumors.« less

Increases of Chamber Height and Base Diameter Have Contrasting Effects on Grazing Rate of Two Cladoceran Species: Implications for Microcosm Studies.

PubMed

Pan, Ying; Zhang, Yunshu; Peng, Yan; Zhao, Qinghua; Sun, Shucun

2015-01-01

Aquatic microcosm studies often increase either chamber height or base diameter (to increase water volume) to test spatial ecology theories such as "scale" effects on ecological processes, but it is unclear whether the increase of chamber height or base diameter have the same effect on the processes, i.e., whether the effect of the shape of three-dimensional spaces is significant. We orthogonally manipulated chamber height and base diameter and determined swimming activity, average swimming velocity and grazing rates of the cladocerans Daphnia magna and Moina micrura (on two algae Scenedesmus quadricauda and Chlorella vulgaris; leading to four aquatic algae-cladoceran systems in total) under different microcosm conditions. Across all the four aquatic systems, increasing chamber height at a given base diameter significantly decreased the duration and velocity of horizontal swimming, and it tended to increase the duration but decrease the velocity of vertical swimming. These collectively led to decreases in both average swimming velocity and grazing rate of the cladocerans in the tall chambers (at a given base diameter), in accordance with the positive relationship between average swimming velocity and grazing rate. In contrast, an increase of base diameter at a given chamber height showed contrasting effects on the above parameters. Consistently, at a given chamber volume increasing ratio of chamber height to base diameter decreased the average swimming velocity and grazing rate across all the aquatic systems. In general, increasing chamber depth and base diameter may exert contrasting effects on zooplankton behavior and thus phytoplankton-zooplankton interactions. We suggest that spatial shape plays an important role in determining ecological process and thus should be considered in a theoretical framework of spatial ecology and also the physical setting of aquatic microcosm experiments.

Increases of Chamber Height and Base Diameter Have Contrasting Effects on Grazing Rate of Two Cladoceran Species: Implications for Microcosm Studies

PubMed Central

Pan, Ying; Zhang, Yunshu; Peng, Yan; Zhao, Qinghua; Sun, Shucun

2015-01-01

Aquatic microcosm studies often increase either chamber height or base diameter (to increase water volume) to test spatial ecology theories such as “scale” effects on ecological processes, but it is unclear whether the increase of chamber height or base diameter have the same effect on the processes, i.e., whether the effect of the shape of three-dimensional spaces is significant. We orthogonally manipulated chamber height and base diameter and determined swimming activity, average swimming velocity and grazing rates of the cladocerans Daphnia magna and Moina micrura (on two algae Scenedesmus quadricauda and Chlorella vulgaris; leading to four aquatic algae-cladoceran systems in total) under different microcosm conditions. Across all the four aquatic systems, increasing chamber height at a given base diameter significantly decreased the duration and velocity of horizontal swimming, and it tended to increase the duration but decrease the velocity of vertical swimming. These collectively led to decreases in both average swimming velocity and grazing rate of the cladocerans in the tall chambers (at a given base diameter), in accordance with the positive relationship between average swimming velocity and grazing rate. In contrast, an increase of base diameter at a given chamber height showed contrasting effects on the above parameters. Consistently, at a given chamber volume increasing ratio of chamber height to base diameter decreased the average swimming velocity and grazing rate across all the aquatic systems. In general, increasing chamber depth and base diameter may exert contrasting effects on zooplankton behavior and thus phytoplankton-zooplankton interactions. We suggest that spatial shape plays an important role in determining ecological process and thus should be considered in a theoretical framework of spatial ecology and also the physical setting of aquatic microcosm experiments. PMID:26273836

Lysine production from methanol at 50 degrees C using Bacillus methanolicus: Modeling volume control, lysine concentration, and productivity using a three-phase continuous simulation.

PubMed

Lee, G H; Hur, W; Bremmon, C E; Flickinger, M C

1996-03-20

A simulation was developed based on experimental data obtained in a 14-L reactor to predict the growth and L-lysine accumulation kinetics, and change in volume of a large-scale (250-m(3)) Bacillus methanolicus methanol-based process. Homoserine auxotrophs of B. methanolicus MGA3 are unique methylotrophs because of the ability to secrete lysine during aerobic growth and threonine starvation at 50 degrees C. Dissolved methanol (100 mM), pH, dissolved oxygen tension (0.063 atm), and threonine levels were controlled to obtain threonine-limited conditions and high-cell density (25 g dry cell weight/L) in a 14-L reactor. As a fed-batch process, the additions of neat methanol (fed on demand), threonine, and other nutrients cause the volume of the fermentation to increase and the final lysine concentration to decrease. In addition, water produced as a result of methanol metabolism contributes to the increase in the volume of the reactor. A three-phase approach was used to predict the rate of change of culture volume based on carbon dioxide production and methanol consumption. This model was used for the evaluation of volume control strategies to optimize lysine productivity. A constant volume reactor process with variable feeding and continuous removal of broth and cells (VF(cstr)) resulted in higher lysine productivity than a fed-batch process without volume control. This model predicts the variation in productivity of lysine with changes in growth and in specific lysine productivity. Simple modifications of the model allows one to investigate other high-lysine-secreting strains with different growth and lysine productivity characteristics. Strain NOA2#13A5-2 which secretes lysine and other end-products were modeled using both growth and non-growth-associated lysine productivity. A modified version of this model was used to simulate the change in culture volume of another L-lysine producing mutant (NOA2#13A52-8A66) with reduced secretion of end-products. The modified simulation indicated that growth-associated production dominates in strain NOA2#13A52-8A66. (c) 1996 John Wiley & Sons, Inc.

Effect of inorganic species on torrefaction process and product properties of rice husk.

PubMed

Zhang, Shuping; Su, Yinhai; Ding, Kuan; Zhu, Shuguang; Zhang, Houlei; Liu, Xinzhi; Xiong, Yuanquan

2018-06-20

The objective of this study was to evaluate the effect of inorganic species on torrefaction process and product properties. Torrefaction process of raw and leached rice husk was performed at different temperatures between 210 and 270 °C. Inorganic species have significant effect on the torrefaction process and properties of torrefaction products. The results indicated that solid yield increased, gas yield decreased and liquid yield remained unchanged for leached rice husk when compared to raw rice husk. Gas products from torrefaction process mainly contained CO 2 and CO, and leaching process slightly reduced the volume concentration of CO 2 . Removal of inorganic species slightly decreased water content and increased organic component content in liquid products. Acetic acid, furfural, 2,3-dihydrobenzofuran and levoglucosan were the dominant components in liquid product. Inorganic species enhanced the effect of deoxygenation and dehydrogenation during torrefaction process, resulting in the enrichment of C component in solid products. Copyright © 2018 Elsevier Ltd. All rights reserved.

Porous carbon material containing CaO for acidic gas capture: preparation and properties.

PubMed

Przepiórski, Jacek; Czyżewski, Adam; Pietrzak, Robert; Toyoda, Masahiro; Morawski, Antoni W

2013-12-15

A one-step process for the preparation of CaO-containing porous carbons is described. Mixtures of poly(ethylene terephthalate) with natural limestone were pyrolyzed and thus hybrid sorbents could be easily obtained. The polymeric material and the mineral served as a carbon precursor and CaO delivering agent, respectively. We discuss effects of the preparation conditions and the relative amounts of the raw materials used for the preparations on the porosity of the hybrid products. The micropore areas and volumes of the obtained products tended to decrease with increasing CaO contents. Increase in the preparation temperature entailed a decrease in the micropore volume, whereas the mesopore volume increased. The pore creation mechanism is proposed on the basis of thermogravimetric and temperature-programmed desorption measurements. The prepared CaO-containing porous carbons efficiently captured SO2 and CO2 from air. Washing out of CaO from the hybrid materials was confirmed as a suitable method to obtain highly porous carbon materials. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of filler content on mechanical and dynamic mechanical properties of particulate biphasic calcium phosphate--polylactide composites.

PubMed

Bleach, N C; Nazhat, S N; Tanner, K E; Kellomäki, M; Törmälä, P

2002-04-01

A bioabsorbable self-reinforced polylactide/biphasic calcium phosphate (BCP) composite is being developed for fracture fixation plates. One manufacturing route is to produce preimpregnated sheets by pulling polylactide (PLA) fibres through a suspension of BCP filler in a PLA solution and compression moulding the prepreg to the desired shape. To aid understanding of the process, interactions between the matrix and filler were investigated. Composite films containing 0-0.25 volume fraction filler, produced by solvent casting, were analysed using SEM, tensile testing and dynamic mechanical analysis (DMA). Homogeneous films could be made, although some particle agglomeration was seen at higher filler volume fractions. As the filler content increased, the failure strain decreased due to a reduction in the amount of ductile polymer present and the ultimate tensile strength (UTS) decreased because of agglomeration and void formation at higher filler content. The matrix glass transition temperature increased due to polymer chain adsorption and immobilization onto the BCP particles. Complex damping mechanisms, such as particle-particle agglomeration, may exist at the higher BCP volume fractions.

National Trends in Prostate Biopsy and Radical Prostatectomy Volumes Following the US Preventive Services Task Force Guidelines Against Prostate-Specific Antigen Screening.

PubMed

Halpern, Joshua A; Shoag, Jonathan E; Artis, Amanda S; Ballman, Karla V; Sedrakyan, Art; Hershman, Dawn L; Wright, Jason D; Shih, Ya Chen Tina; Hu, Jim C

2017-02-01

Studies demonstrate that use of prostate-specific antigen screening decreased significantly following the US Preventive Services Task Force (USPSTF) recommendation against prostate-specific antigen screening in 2012. To determine downstream effects on practice patterns in prostate cancer diagnosis and treatment following the 2012 USPSTF recommendation. Procedural volumes of certifying and recertifying urologists from 2009 through 2016 were evaluated for variation in prostate biopsy and radical prostatectomy (RP) volume. Trends were confirmed using the New York Statewide Planning and Research Cooperative System and Nationwide Inpatient Sample. The study included a representative sample of urologists across practice settings and nationally representative sample of all RP discharges. We obtained operative case logs from the American Board of Urology and identified urologists performing at least 1 prostate biopsy (n = 5173) or RP (n = 3748), respectively. The 2012 USPSTF recommendation against routine population-wide prostate-specific antigen screening. Change in median biopsy and RP volume per urologist and national procedural volume. Following the USPSTF recommendation, median biopsy volume per urologist decreased from 29 to 21 (interquartile range [IQR}, 12-34; P < .001). After adjusting for physician and practice characteristics, biopsy volume decreased by 28.7% following 2012 (parameter estimate, -0.25; SE, 0.03; P < .001). Similarly, following the USPSTF recommendation, median RP volume per urologist decreased from 7 (IQR, 3-15) to 6 (IQR, 2-12) (P < .001), and in adjusted analyses, RP volume decreased 16.2% (parameter estimate, -0.15; SE, 0.05; P = .003). Following the 2012 USPSTF recommendation, prostate biopsy and RP volumes decreased significantly. A panoramic vantage point is needed to evaluate the long-term consequences of the 2012 USPSTF recommendation.

Differential effects of lower body negative pressure and upright tilt on splanchnic blood volume

PubMed Central

Taneja, Indu; Moran, Christopher; Medow, Marvin S.; Glover, June L.; Montgomery, Leslie D.; Stewart, Julian M.

2015-01-01

Upright posture and lower body negative pressure (LBNP) both induce reductions in central blood volume. However, regional circulatory responses to postural changes and LBNP may differ. Therefore, we studied regional blood flow and blood volume changes in 10 healthy subjects undergoing graded lower-body negative pressure (−10 to −50 mmHg) and 8 subjects undergoing incremental head-up tilt (HUT; 20°, 40°, and 70°) on separate days. We continuously measured blood pressure (BP), heart rate, and regional blood volumes and blood flows in the thoracic, splanchnic, pelvic, and leg segments by impedance plethysmography and calculated regional arterial resistances. Neither LBNP nor HUT altered systolic BP, whereas pulse pressure decreased significantly. Blood flow decreased in all segments, whereas peripheral resistances uniformly and significantly increased with both HUT and LBNP. Thoracic volume decreased while pelvic and leg volumes increased with HUT and LBNP. However, splanchnic volume changes were directionally opposite with stepwise decreases in splanchnic volume with LBNP and stepwise increases in splanchnic volume during HUT. Splanchnic emptying in LBNP models regional vascular changes during hemorrhage. Splanchnic filling may limit the ability of the splanchnic bed to respond to thoracic hypovolemia during upright posture. PMID:17085534

A Biphasic Change of Regional Blood Volume in the Frontal Cortex during Non-Rapid Eye Movement Sleep: A Near-Infrared Spectroscopy Study.

PubMed

Zhang, Zhongxing; Khatami, Ramin

2015-08-01

Current knowledge on hemodynamics in sleep is limited because available techniques do not allow continuous recordings and mainly focus on cerebral blood flow while neglecting other important parameters, such as blood volume (BV) and vasomotor activity. Observational study. Continuous measures of hemodynamics over the left forehead and biceps were performed using near-infrared spectroscopy (NIRS) during nocturnal polysomnography in 16 healthy participants in sleep laboratory. Temporal dynamics and mean values of cerebral and muscular oxygenated hemoglobin (HbO2), deoxygenated hemoglobin (HHb), and BV during different sleep stages were compared. A biphasic change of cerebral BV was observed which contrasted a monotonic increase of muscular BV during non-rapid eye movement sleep. A significant decrement in cerebral HbO2 and BV accompanied by an increase of HHb was recorded at sleep onset (Phase I). Prior to slow wave sleep (SWS) HbO2 and BV turned to increase whereas HHb began to decrease in subsequent Phase II suggested increased brain perfusion during SWS. The cerebral HbO2 slope correlated to BV slope in Phase I and II, but it only correlated to HHb slope in Phase II. The occurrence time of inflection points correlated to SWS latencies. Initial decrease of brain perfusion with decreased blood volume (BV) and oxygenated hemoglobin (HbO2) together with increasing muscular BV fit thermoregulation process at sleep onset. The uncorrelated and correlated slopes of HbO2 and deoxygenated hemoglobin indicate different mechanisms underlying the biphasic hemodynamic process in light sleep and slow wave sleep (SWS). In SWS, changes in vasomotor activity (i.e., increased vasodilatation) may mediate increasing cerebral and muscular BV. © 2015 Associated Professional Sleep Societies, LLC.

Inhibition of Regulatory Volume Decrease Enhances the Cytocidal Effect of Hypotonic Shock in Hepatocellular Carcinoma.

PubMed

Kudou, Michihiro; Shiozaki, Atsushi; Kosuga, Toshiyuki; Ichikawa, Daisuke; Konishi, Hirotaka; Morimura, Ryo; Komatsu, Shuhei; Ikoma, Hisashi; Fujiwara, Hitoshi; Okamoto, Kazuma; Hosogi, Shigekuni; Nakahari, Takashi; Marunaka, Yoshinori; Otsuji, Eigo

2016-01-01

Background : Hypotonic shock induces cytocidal effects through cell rupture, and cancer therapy based on this mechanism has been clinically administered to hepatocellular carcinoma patients. We herein investigated the effectiveness of hypotonic shock combined with the inhibition of regulatory volume decrease as cancer therapy for hepatocellular carcinoma. Methods : Morphological changes in human hepatocellular carcinoma cell lines were observed under a differential interference contrast microscope connected to a high-speed digital video camera. Cell volume changes under hypotonic shock with or without chloride, potassium, or water channel blockers were observed using a high-resolution flow cytometer. In order to investigate cytocidal effects, the number of surviving cells was compared after exposure to hypotonic solution with and without each channel blocker (re-incubation experiment). Results : Video recordings showed that cells exposed to distilled water rapidly swelled and then ruptured. Cell volume measurements revealed regulatory volume decrease under mild hypotonic shock, whereas severe hypotonic shock increased the number of broken fragments as a result of cell rupture. Moreover, regulatory volume decrease was inhibited in cells treated with each channel blocker. Re-incubation experiments showed the cytocidal effects of hypotonic shock in cells exposed to hypotonic solution, and additional treatments with each channel blocker enhanced these effects. Conclusion : The inhibition of regulatory volume decrease with chloride, potassium, or water channel blockers may enhance the cytocidal effects of hypotonic shock in hepatocellular carcinoma. Hypotonic shock combined with the inhibition of regulatory volume decrease was a more effective therapy than hypotonic shock alone.

Inhibition of Regulatory Volume Decrease Enhances the Cytocidal Effect of Hypotonic Shock in Hepatocellular Carcinoma

PubMed Central

Kudou, Michihiro; Shiozaki, Atsushi; Kosuga, Toshiyuki; Ichikawa, Daisuke; Konishi, Hirotaka; Morimura, Ryo; Komatsu, Shuhei; Ikoma, Hisashi; Fujiwara, Hitoshi; Okamoto, Kazuma; Hosogi, Shigekuni; Nakahari, Takashi; Marunaka, Yoshinori; Otsuji, Eigo

2016-01-01

Background: Hypotonic shock induces cytocidal effects through cell rupture, and cancer therapy based on this mechanism has been clinically administered to hepatocellular carcinoma patients. We herein investigated the effectiveness of hypotonic shock combined with the inhibition of regulatory volume decrease as cancer therapy for hepatocellular carcinoma. Methods: Morphological changes in human hepatocellular carcinoma cell lines were observed under a differential interference contrast microscope connected to a high-speed digital video camera. Cell volume changes under hypotonic shock with or without chloride, potassium, or water channel blockers were observed using a high-resolution flow cytometer. In order to investigate cytocidal effects, the number of surviving cells was compared after exposure to hypotonic solution with and without each channel blocker (re-incubation experiment). Results: Video recordings showed that cells exposed to distilled water rapidly swelled and then ruptured. Cell volume measurements revealed regulatory volume decrease under mild hypotonic shock, whereas severe hypotonic shock increased the number of broken fragments as a result of cell rupture. Moreover, regulatory volume decrease was inhibited in cells treated with each channel blocker. Re-incubation experiments showed the cytocidal effects of hypotonic shock in cells exposed to hypotonic solution, and additional treatments with each channel blocker enhanced these effects. Conclusion: The inhibition of regulatory volume decrease with chloride, potassium, or water channel blockers may enhance the cytocidal effects of hypotonic shock in hepatocellular carcinoma. Hypotonic shock combined with the inhibition of regulatory volume decrease was a more effective therapy than hypotonic shock alone. PMID:27471568

Decreased contralateral breast volume after mastectomy, adjuvant chemotherapy, and anti-estrogen therapy, in particular in breasts with high density.

PubMed

Ishii, Naohiro; Ando, Jiro; Harao, Michiko; Takemae, Masaru; Kishi, Kazuo

2017-10-01

Adjuvant chemotherapy and anti-estrogenic therapy can result in decreased volume of the contralateral breast, following mastectomy for the treatment of breast cancer. However, no data on the effect of adjuvant therapy on contralateral breast volume have previously been reported. We aimed to evaluate the extent to which adjuvant therapy and differences in breast density contribute to decreased breast volume. We conducted a prospective cohort study, selecting 40 nonconsecutive patients who underwent immediate breast reconstruction with mastectomy and expander insertion followed by expander replacement. We measured the contralateral breast volume before each procedure. The extent of the change was analyzed with respect to adjuvant therapy and breast density measured by preoperative mammography. The greatest decrease in breast volume was 135.1 cm 3 . The decrease in breast volume was significantly larger in the adjuvant therapy (+) group, particularly in patients with high breast density, than in the adjuvant therapy (-) group. Significant differences between the chemotherapy (+), tamoxifen (+) group and the chemotherapy (-), tamoxifen (+) group were not found. Breast density scores had a range of 2.0-3.3 (mean: 2.8). In breast reconstruction, particularly when performed in one stage, preoperative mammography findings are valuable to plastic surgeons, and possible decreases in the contralateral breast volume due to adjuvant therapy, particularly in patients with high breast density, should be considered carefully. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Modulation of red cell mass by neocytolysis in space and on Earth

NASA Technical Reports Server (NTRS)

Rice, L.; Alfrey, C. P.

2000-01-01

Astronauts predictably experience anemia after return from space. Upon entering microgravity, the blood volume in the extremities pools centrally and plasma volume decreases, causing plethora and erythropoietin suppression. There ensues neocytolysis, selective hemolysis of the youngest circulating red cells, allowing rapid adaptation to the space environment but becoming maladaptive on re-entry to a gravitational field. The existence of this physiologic control process was confirmed in polycythemic high-altitude dwellers transported to sea level. Pathologic neocytolysis contributes to the anemia of renal failure. Understanding the process has implications for optimizing erythropoietin-dosing schedules and the therapy of other human disorders. Human and rodent models of neocytolysis are being created to help find out how interactions between endothelial cells, reticuloendothelial phagocytes and young erythrocytes are altered, and to shed light on the expression of surface adhesion molecules underlying this process. Thus, unraveling a problem for space travelers has uncovered a physiologic process controlling the red cell mass that can be applied to human disorders on Earth.

Microstructural and bulk property changes in hardened cement paste during the first drying process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maruyama, Ippei, E-mail: ippei@dali.nuac.nagoya-u.ac.jp; Nishioka, Yukiko; Igarashi, Go

2014-04-01

This paper reports the microstructural changes and resultant bulk physical property changes in hardened cement paste (hcp) during the first desorption process. The microstructural changes and solid-phase changes were evaluated by water vapor sorption, nitrogen sorption, ultrasonic velocity, and {sup 29}Si and {sup 27}Al nuclear magnetic resonance. Strength, Young's modulus, and drying shrinkage were also examined. The first drying process increased the volume of macropores and decreased the volume of mesopores and interlayer spaces. Furthermore, in the first drying process globule clusters were interconnected. During the first desorption, the strength increased for samples cured at 100% to 90% RH, decreasedmore » for 90% to 40% RH, and increased again for 40% to 11% RH. This behavior is explained by both microstructural changes in hcp and C–S–H globule densification. The drying shrinkage strains during rapid drying and slow drying were compared and the effects of the microstructural changes and evaporation were separated.« less

Anosmia leads to a loss of gray matter in cortical brain areas.

PubMed

Bitter, Thomas; Gudziol, Hilmar; Burmeister, Hartmut Peter; Mentzel, Hans-Joachim; Guntinas-Lichius, Orlando; Gaser, Christian

2010-06-01

Chronic olfactory disorders, including the complete loss of the sense of smell (anosmia), are common. Using voxel-based morphometry (VBM) in magnetic resonance imaging (MRI), structural changes in the cerebral gray matter (GM) of a group of patients with anosmia compared with a normosmic, healthy control group were evaluated. Patients with anosmia presented a significant decrease of GM volume mainly in the nucleus accumbens with adjacent subcallosal gyrus, in the medial prefrontal cortex (MPC) including the middle and anterior cingulate cortices, and in the dorsolateral prefrontal cortex (dlPFC). These areas are part of the limbic loop of the basal ganglia and except the dlPFC secondary olfactory areas. They also play an important role in many neurological diseases. Furthermore, volume decreases in smaller areas like the piriform cortex, insular cortex, orbitofrontal cortex, hippocampus, parahippocampal gyrus, supramarginal gyrus, and cerebellum could be seen. Longer disease duration was associated with a stronger atrophy in the described areas. No local increases in the GM volume could be observed. A comparison with results of an additionally executed functional MRI study on olfaction in healthy subjects was performed to evaluate the significance of the observed atrophy areas in cerebral olfactory processing. To our knowledge, this is the first study on persisting structural changes in cortical GM volume after complete olfactory loss.

Miniaturization Technologies for Efficient Single-Cell Library Preparation for Next-Generation Sequencing.

PubMed

Mora-Castilla, Sergio; To, Cuong; Vaezeslami, Soheila; Morey, Robert; Srinivasan, Srimeenakshi; Dumdie, Jennifer N; Cook-Andersen, Heidi; Jenkins, Joby; Laurent, Louise C

2016-08-01

As the cost of next-generation sequencing has decreased, library preparation costs have become a more significant proportion of the total cost, especially for high-throughput applications such as single-cell RNA profiling. Here, we have applied novel technologies to scale down reaction volumes for library preparation. Our system consisted of in vitro differentiated human embryonic stem cells representing two stages of pancreatic differentiation, for which we prepared multiple biological and technical replicates. We used the Fluidigm (San Francisco, CA) C1 single-cell Autoprep System for single-cell complementary DNA (cDNA) generation and an enzyme-based tagmentation system (Nextera XT; Illumina, San Diego, CA) with a nanoliter liquid handler (mosquito HTS; TTP Labtech, Royston, UK) for library preparation, reducing the reaction volume down to 2 µL and using as little as 20 pg of input cDNA. The resulting sequencing data were bioinformatically analyzed and correlated among the different library reaction volumes. Our results showed that decreasing the reaction volume did not interfere with the quality or the reproducibility of the sequencing data, and the transcriptional data from the scaled-down libraries allowed us to distinguish between single cells. Thus, we have developed a process to enable efficient and cost-effective high-throughput single-cell transcriptome sequencing. © 2016 Society for Laboratory Automation and Screening.

Quantitative and qualitative analysis of bone flap resorption in patients undergoing cranioplasty after decompressive craniectomy.

PubMed

Korhonen, Tommi K; Salokorpi, Niina; Niinimäki, Jaakko; Serlo, Willy; Lehenkari, Petri; Tetri, Sami

2018-02-23

OBJECTIVE Autologous bone cranioplasty after decompressive craniectomy entails a notable burden of difficult postoperative complications, such as infection and bone flap resorption (BFR), leading to mechanical failure. The prevalence and significance of asymptomatic BFR is currently unclear. The aim of this study was to radiologically monitor the long-term bone flap survival and bone quality change in patients undergoing autologous cranioplasty. METHODS The authors identified all 45 patients who underwent autologous cranioplasty at Oulu University Hospital, Finland, between January 2004 and December 2014. Using perioperative and follow-up CT scans, the volumes and radiodensities of the intact bone flap prior to surgery and at follow-up were calculated. Relative changes in bone flap volume and radiodensity were then determined to assess cranioplasty survival. Sufficient CT scans were obtainable from 41 (91.1%) of the 45 patients. RESULTS The 41 patients were followed up for a median duration of 3.79 years (25th and 75th percentiles = 1.55 and 6.66). Thirty-seven (90.2%) of the 41 patients had some degree of BFR and 13 (31.7%) had a remaining bone flap volume of less than 80%. Patients younger than 30 years of age had a mean decrease of 15.8% in bone flap volume compared with the rest of the cohort. Bone flap volume was not found to decrease linearly with the passing of time, however. The effects of lifestyle factors and comorbidities on BFR were nonsignificant. CONCLUSIONS In this study BFR was a very common phenomenon, occurring at least to some degree in 90% of the patients. Decreases in bone volume were especially prominent in patients younger than 30 years of age. Because the progression of resorption during follow-up was nonlinear, routine follow-up CT scans appear unnecessary in monitoring the progression of BFR; instead, clinical follow-up with mechanical stability assessment is advised. Partial resorption is most likely a normal physiological phenomenon during the bone revitalization process.

Visuospatial processing in children with neurofibromatosis type 1

PubMed Central

Clements-Stephens, Amy M.; Rimrodt, Sheryl L.; Gaur, Pooja; Cutting, Laurie E.

2008-01-01

Neuroimaging studies investigating the neural network of visuospatial processing have revealed a right hemisphere network of activation including inferior parietal lobe, dorsolateral prefrontal cortex, and extrastriate regions. Impaired visuospatial processing, indicated by the Judgment of Line Orientation (JLO), is commonly seen in individuals with Neurofibromatosis type 1 (NF-1). Nevertheless, few studies have examined the neural activity associated with visuospatial processing in NF-1, in particular, during a JLO task. This study used functional neuroimaging to explore differences in volume of activation in predefined regions of interest between 13 individuals with NF-1 and 13 controls while performing an analogue JLO task. We hypothesized that participants with NF-1 would show anomalous right hemisphere activation and therefore would recruit regions within the left hemisphere to complete the task. Multivariate analyses of variance were used to test for differences between groups in frontal, temporal, parietal, and occipital regions. Results indicate that, as predicted, controls utilized various right hemisphere regions to complete the task, while the NF-1 group tended to recruit left hemisphere regions. These results suggest that the NF-1 group has an inefficient right hemisphere network. An additional unexpected finding was that the NF-1 group showed decreased volume of activation in primary visual cortex (BA 17). Future studies are needed to examine whether the decrease in primary visual cortex is related to a deficit in basic visual processing; findings could ultimately lead to a greater understanding of the nature of deficits in NF-1 and have implications for remediation. PMID:17988695

Army Sustainment. Volume 43, Issue 3, May-June 2011

DTIC Science & Technology

2011-06-01

data entry, which produces a decrease in errors and also an increase in efficiency because automatic reading saves time . Today’s RFID...company, and even pla- toon, level . This push does not necessarily call for drastic adjustments to the personnel and equipment structure of the company...specialists. This increased capability would allow more streamlined processes for submitting

Field tests prove microscale NRU to upgrade low-btu gas

USGS Publications Warehouse

Bhattacharya, Saibal; Newell, K. David; Watney, W. Lynn; Sigel, Micael

2009-01-01

The Kansas Geological Survey (University of Kansas) and the American Energies Corp., Wichita, have conducted field tests of a scalable, microscale, N2-rejection unit (NRU) to demonstrate its effectiveness to upgrade low-pressure ((<100 psig) and low-volume (=100 Mcfd) low-btu gas to pipeline quality. The tests aim to develop inexpensive NRU technology, which is designed for low- volume, low-pressure gas wells, to significantly increase the contribution of marginal low-btu gas to the gas supply of the US. The NRU uses two towers and uses three stages, namely, adsorption under pressure, venting to 2 psig, and desorption under vacuum. The modular design allows additional sets of towers to be added or removed to handle increases or decreases in feed volumes. The field tests also reveal that a strong compressor, which is capable of evacuating the tower (volume) as quickly as possible, should be employed to reduce process cycle time and increase plant throughput.

MR volumetric analysis of the course of nephroblastomatosis under chemotherapy in childhood.

PubMed

Günther, Patrick; Tröger, Jochen; Graf, Norbert; Waag, Karl Ludwig; Schenk, Jens-Peter

2004-08-01

Nephroblastomatosis is a paediatric renal disease that may undergo malignant transformation. When neoadjuvant chemotherapy is indicated for nephroblastomatosis or bilateral Wilms' tumours, exact volumetric analysis using high-speed data processing and visualization may aid in determining tumour response. Using 3D-volume-rendering software, the 0.5-T MRI data of a 2-year-old girl with bilateral nephroblastomatosis was analysed. Exact volume determination of foci of nephroblastomatosis was performed by automatic and manual segmentation, and the relation to normal renal parenchyma was determined over a 12-month period. At the first visit, 80% (460/547 ml) of the extremely enlarged right kidney was due to nephroblastomatosis. Total tumour volume within the right kidney decreased to 74 ml under chemotherapy. Volume analysis of the two emerging right-sided masses after treatment correctly suggested Wilms' tumour. Three-dimensional rendering of the growing masses aided the surgeon in nephron-sparing surgery during tumour resection.

Codeformation processing of mechanically-dissimilar metal/intermetallic composites

NASA Astrophysics Data System (ADS)

Marte, Judson Sloan

A systematic and scientific approach has been applied to the study of codeformation processing. A series of composites having mechanically-dissimilar phases were developed in which the high temperature flow behavior of the reinforcement material could be varied independent of the matrix. This was accomplished through the use of a series of intermetallic matrix composites (IMCs) as discontinuous reinforcements in an otherwise conventional metal matrix composite. The IMCs are produced using an in-situ reaction synthesis technique, called the XD(TM) process. The temperature of the exothermic synthesis reaction, called the adiabatic temperature, has been calculated and shown to increase with increasing volume percentage of TiB2 reinforcement. Further, this temperature has been shown to effect the size and spacing of the TiB2, microstructural features which are often used in discontinuous composite strength models. Study of the high temperature flow behavior of the components of the metal/IMC composite is critical to the development of an understanding of codeformation. A series of compression tests performed at 1000° to 1200°C and strain-rates of 10-3 and 10-4 sec-1. Peak flow stresses were used to evaluate the influence of material properties and process conditions. These data were incorporated into phenomenologically-based constitutive equations that have been used to predict the flow behavior. It has been determined that plastic deformation of the IMCs occurs readily, and is largely TiB2 independent, at temperatures approaching the melting point of the intermetallic matrices. Ti-6Al-4V/IMC powder blends were extruded at high temperatures to achieve commensurately deformed microstructures. The results of codeformation processing were analyzed in terms of the plastic strain of the IMC particulates. IMC particle deformation was shown to increase with increasing IMC particle size, volume percentage of IMC, extrusion temperature, homologous temperature, extrusion strain-rate, and decreasing TiB2 reinforcement within the IMCs. A series of finite element models were developed to simulate codeformation processing via the extrusion of a discontinuously-reinforced composite. The results were evaluated through comparison between average equivalent strain in matrix and reinforcement elements. These results show that codeformation should increase with increasing volume percentage of IMC, homologous temperature, volume percentage of IMC, and decreasing IMC particle size. With the exception of the particle size, these results correlate to those of the experimental extrusion analysis.

Ventilation rates and activity levels of juvenile jumbo squid under metabolic suppression in the oxygen minimum zone.

PubMed

Trübenbach, Katja; Pegado, Maria R; Seibel, Brad A; Rosa, Rui

2013-02-01

The Humboldt (jumbo) squid, Dosidicus gigas, is a part-time resident of the permanent oxygen minimum zone (OMZ) in the Eastern Tropical Pacific and, thereby, it encounters oxygen levels below its critical oxygen partial pressure. To better understand the ventilatory mechanisms that accompany the process of metabolic suppression in these top oceanic predators, we exposed juvenile D. gigas to the oxygen levels found in the OMZ (1% O(2), 1 kPa, 10 °C) and measured metabolic rate, activity cycling patterns, swimming mode, escape jet (burst) frequency, mantle contraction frequency and strength, stroke volume and oxygen extraction efficiency. In normoxia, metabolic rate varied between 14 and 29 μmol O(2) g(-1) wet mass h(-1), depending on the level of activity. The mantle contraction frequency and strength were linearly correlated and increased significantly with activity level. Additionally, an increase in stroke volume and ventilatory volume per minute was observed, followed by a mantle hyperinflation process during high activity periods. Squid metabolic rate dropped more than 75% during exposure to hypoxia. Maximum metabolic rate was not achieved under such conditions and the metabolic scope was significantly decreased. Hypoxia changed the relationship between mantle contraction strength and frequency from linear to polynomial with increasing activity, indicating that, under hypoxic conditions, the jumbo squid primarily increases the strength of mantle contraction and does not regulate its frequency. Under hypoxia, jumbo squid also showed a larger inflation period (reduced contraction frequency) and decreased relaxed mantle diameter (shortened diffusion pathway), which optimize oxygen extraction efficiency (up to 82%/34%, without/with consideration of 60% potential skin respiration). Additionally, they breathe 'deeply', with more powerful contractions and enhanced stroke volume. This deep-breathing behavior allows them to display a stable ventilatory volume per minute, and explains the maintenance of the squid's cycling activity under such O(2) conditions. During hypoxia, the respiratory cycles were shorter in length but increased in frequency. This was accompanied by an increase in the number of escape jets during active periods and a faster switch between swimming modes. In late hypoxia (onset ~170 ± 10 min), all the ventilatory processes were significantly reduced and followed by a lethargic state, a behavior that seems closely associated with the process of metabolic suppression and enables the squid to extend its residence time in the OMZ.

Effect of Ni Addition on Bainite Transformation and Properties in a 2000 MPa Grade Ultrahigh Strength Bainitic Steel

NASA Astrophysics Data System (ADS)

Tian, Junyu; Xu, Guang; Jiang, Zhengyi; Hu, Haijiang; Zhou, Mingxing

2018-05-01

The effects of Nickle (Ni) addition on bainitic transformation and property of ultrahigh strength bainitic steels are investigated by three austempering processes. The results indicate that Ni addition hinders the isothermal bainite transformation kinetics, and decreases the volume fraction of bainite due to the decrease of chemical driving force for nucleation and growth of bainite transformation. Moreover, the product of tensile strength and total elongation (PSE) of high carbon bainitic steels decreases with Ni addition at higher austempering temperatures (220 and 250 °C), while it shows no significant difference at lower austempering temperature (200 °C). For the same steel (Ni-free or Ni-added steel), the amounts of bainite and RA firstly increase and then decrease with the increase of the austempering temperature, resulting in the highest PSE in the sample austempered at temperature of 220 °C. In addition, the effects of austempering time on bainite amount and property of high carbon bainitic steels are also analyzed. It indicates that in a given transformation time range of 30 h, more volume of bainite and better mechanical property in high carbon bainitic steels can be obtained by increasing the isothermal transformation time.

Worse Neurological State During Acute Ischemic Stroke is Associated with a Decrease in Serum Albumin Levels.

PubMed

Bielewicz, Joanna; Kurzepa, Jacek; Czekajska-Chehab, Elżbieta; Kamieniak, Piotr; Daniluk, Beata; Bartosik-Psujek, Halina; Rejdak, Konrad

2016-04-01

High serum albumin levels during ischemic stroke (IS) decrease the risk of a poor outcome. This study aimed to determine whether serum albumin levels within the first days after IS correlate with radiological and biochemical markers of brain tissue damage. Fifty-six IS patients were enrolled into the study. Neurological examinations were based on the National Institute of Health Stroke Scale. Serum albumin levels and S100BB were evaluated using commercially available ELISA kits. The albumin decrease index (ADI) was calculated as the difference between serum albumin levels measured on days 1 and 10 of IS. All parameters were estimated on the 1st, 3rd, 5th, and 10th days of IS, and the volume of ischemic focus was measured on the 10th day. Mean serum albumin levels were decreased during acute IS. There were correlations between the ADI and mean S100BB serum levels (r = 0.36, p < 0.05), the volume of ischemic focus (r = 0.39, p < 0.05), and the patients' neurological state when measured on day 10 of IS (r = 0.59, p < 0.001). A decrease in serum albumin levels during the acute phase of IS corresponds to a worse neurological state as a result of a large ischemic focus with intense catabolic processes.

Longitudinal Study of Gray Matter Changes in Parkinson Disease.

PubMed

Jia, X; Liang, P; Li, Y; Shi, L; Wang, D; Li, K

2015-12-01

The pathology of Parkinson disease leads to morphological brain volume changes. So far, the progressive gray matter volume change across time specific to patients with Parkinson disease compared controls remains unclear. Our aim was to investigate the pattern of gray matter changes in patients with Parkinson disease and to explore the progressive gray matter volume change specific to patients with Parkinson disease with disease progression by using voxel-based morphometry analysis. Longitudinal cognitive assessment and structural MR imaging of 89 patients with Parkinson disease (62 men) and 55 healthy controls (33 men) were from the Parkinson's Progression Markers Initiative data base, including the initial baseline and 12-month follow-up data. Two-way analysis of covariance was performed with covariates of age, sex, years of education, imaging data from multiple centers, and total intracranial volume by using Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra tool from SPM8 software. Gray matter volume changes for patients with Parkinson disease were detected with decreased gray matter volume in the frontotemporoparietal areas and the bilateral caudate, with increased gray matter volume in the bilateral limbic/paralimbic areas, medial globus pallidus/putamen, and the right occipital cortex compared with healthy controls. Progressive gray matter volume decrease in the bilateral caudate was found for both patients with Parkinson disease and healthy controls, and this caudate volume was positively associated with cognitive ability for both groups. The progressive gray matter volume increase specific to the patients with Parkinson disease was identified close to the left ventral lateral nucleus of thalamus, and a positive relationship was found between the thalamic volume and the tremor scores in a subgroup with tremor-dominant patients with Parkinson disease. The observed progressive changes in gray matter volume in Parkinson disease may provide new insights into the neurodegenerative process. The current findings suggest that the caudate volume loss may contribute to cognitive decline in patients with Parkinson disease and the progressive thalamus enlargement may have relevance to tremor severity in Parkinson disease. © 2015 by American Journal of Neuroradiology.

Preparation and Anodizing of SiCp/Al Composites with Relatively High Fraction of SiCp

PubMed Central

2018-01-01

By properly proportioned SiC particles with different sizes and using squeeze infiltration process, SiCp/Al composites with high volume fraction of SiC content (Vp = 60.0%, 61.2%, 63.5%, 67.4%, and 68.0%) were achieved for optical application. The flexural strength of the prepared SiCp/Al composites was higher than 483 MPa and the elastic modulus was increased from 174.2 to 206.2 GPa. With an increase in SiC volume fraction, the flexural strength and Poisson's ratio decreased with the increase in elastic modulus. After the anodic oxidation treatment, an oxidation film with porous structure was prepared on the surface of the composite and the oxidation film was uniformly distributed. The anodic oxide growth rate of composite decreased with SiC content increased and linearly increased with anodizing time. PMID:29682145

Preparation and Anodizing of SiCp/Al Composites with Relatively High Fraction of SiCp.

PubMed

Wang, Bin; Qu, Shengguan; Li, Xiaoqiang

2018-01-01

By properly proportioned SiC particles with different sizes and using squeeze infiltration process, SiCp/Al composites with high volume fraction of SiC content (Vp = 60.0%, 61.2%, 63.5%, 67.4%, and 68.0%) were achieved for optical application. The flexural strength of the prepared SiC p /Al composites was higher than 483 MPa and the elastic modulus was increased from 174.2 to 206.2 GPa. With an increase in SiC volume fraction, the flexural strength and Poisson's ratio decreased with the increase in elastic modulus. After the anodic oxidation treatment, an oxidation film with porous structure was prepared on the surface of the composite and the oxidation film was uniformly distributed. The anodic oxide growth rate of composite decreased with SiC content increased and linearly increased with anodizing time.

Effects of gestational age on brain volume and cognitive functions in generally healthy very preterm born children during school-age: A voxel-based morphometry study.

PubMed

Lemola, Sakari; Oser, Nadine; Urfer-Maurer, Natalie; Brand, Serge; Holsboer-Trachsler, Edith; Bechtel, Nina; Grob, Alexander; Weber, Peter; Datta, Alexandre N

2017-01-01

To determine whether the relationship of gestational age (GA) with brain volumes and cognitive functions is linear or whether it follows a threshold model in preterm and term born children during school-age. We studied 106 children (M = 10 years 1 month, SD = 16 months; 40 females) enrolled in primary school: 57 were healthy very preterm children (10 children born 24-27 completed weeks' gestation (extremely preterm), 14 children born 28-29 completed weeks' gestation, 19 children born 30-31 completed weeks' gestation (very preterm), and 14 born 32 completed weeks' gestation (moderately preterm)) all born appropriate for GA (AGA) and 49 term-born children. Neuroimaging involved voxel-based morphometry with the statistical parametric mapping software. Cognitive functions were assessed with the WISC-IV. General Linear Models and multiple regressions were conducted controlling age, sex, and maternal education. Compared to groups of children born 30 completed weeks' gestation and later, children born <28 completed weeks' gestation had less gray matter volume (GMV) and white matter volume (WMV) and poorer cognitive functions including decreased full scale IQ, and processing speed. Differences in GMV partially mediated the relationship between GA and full scale IQ in preterm born children. In preterm children who are born AGA and without major complications GA is associated with brain volume and cognitive functions. In particular, decreased brain volume becomes evident in the extremely preterm group (born <28 completed weeks' gestation). In preterm children born 30 completed weeks' gestation and later the relationship of GA with brain volume and cognitive functions may be less strong as previously thought.

Solid recovered fuel production from biodegradable waste in grain processing industry.

PubMed

Kliopova, Irina; Staniskis, Jurgis Kazimieras; Petraskiene, Violeta

2013-04-01

Management of biodegradable waste is one of the most important environmental problems in the grain-processing industry since this waste cannot be dumped anymore due to legal requirements. Biodegradable waste is generated in each stage of grain processing, including the waste-water and air emissions treatment processes. Their management causes some environmental and financial problems. The majority of Lithuanian grain-processing enterprises own and operate composting sites, but in Lithuania the demand for compost is not given. This study focused on the analysis of the possibility of using biodegradable waste for the production of solid recovered fuel, as a local renewable fuel with the purpose of increasing environmental performance and decreasing the direct costs of grain processing. Experimental research with regard to a pilot grain-processing plant has proven that alternative fuel production will lead to minimizing of the volume of biodegradable waste by 75% and the volume of natural gas for heat energy production by 62%. Environmental indicators of grain processing, laboratory analysis of the chemical and physical characteristics of biodegradable waste, mass and energy balances of the solid recovered fuel production, environmental and economical benefits of the project are presented and discussed herein.

Classifying adolescent attention-deficit/hyperactivity disorder (ADHD) based on functional and structural imaging.

PubMed

Iannaccone, Reto; Hauser, Tobias U; Ball, Juliane; Brandeis, Daniel; Walitza, Susanne; Brem, Silvia

2015-10-01

Attention-deficit/hyperactivity disorder (ADHD) is a common disabling psychiatric disorder associated with consistent deficits in error processing, inhibition and regionally decreased grey matter volumes. The diagnosis is based on clinical presentation, interviews and questionnaires, which are to some degree subjective and would benefit from verification through biomarkers. Here, pattern recognition of multiple discriminative functional and structural brain patterns was applied to classify adolescents with ADHD and controls. Functional activation features in a Flanker/NoGo task probing error processing and inhibition along with structural magnetic resonance imaging data served to predict group membership using support vector machines (SVMs). The SVM pattern recognition algorithm correctly classified 77.78% of the subjects with a sensitivity and specificity of 77.78% based on error processing. Predictive regions for controls were mainly detected in core areas for error processing and attention such as the medial and dorsolateral frontal areas reflecting deficient processing in ADHD (Hart et al., in Hum Brain Mapp 35:3083-3094, 2014), and overlapped with decreased activations in patients in conventional group comparisons. Regions more predictive for ADHD patients were identified in the posterior cingulate, temporal and occipital cortex. Interestingly despite pronounced univariate group differences in inhibition-related activation and grey matter volumes the corresponding classifiers failed or only yielded a poor discrimination. The present study corroborates the potential of task-related brain activation for classification shown in previous studies. It remains to be clarified whether error processing, which performed best here, also contributes to the discrimination of useful dimensions and subtypes, different psychiatric disorders, and prediction of treatment success across studies and sites.

Structure of AA5056 after friction drilling

NASA Astrophysics Data System (ADS)

Eliseev, A. A.; Kalashnikova, T. A.; Fortuna, S. V.

2017-12-01

Here we present data on the structure of AA5056 alloy after friction drilling to unveil potentials of the process for use in model experiments on friction stir welding. Our analysis of the average size and volume content of precipitates shows that their content decreases immediately beneath the friction surface and that the structure of this zone is the same as the structure of stirring zones formed in friction stir welding. The data suggest that both processes provide similar metal structures.

A Method for Out-of-autoclave Fabrication of High Fiber Volume Fraction Fiber Reinforced Polymer Composites

DTIC Science & Technology

2012-07-01

Composites 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Larry R. Holmes, Jr., James P. Wolbert, and Jared M...greater than 10 kPa (1.5 psi) pressure change in the vacuum bag. A redundant second vacuum bag was applied over the entire layup to further protect...In order to maintain the increased fvf and decrease the processing time, a second experimental process was conducted using a compacted and pre

Evaluation of whole genome amplified DNA to decrease material expenditure and increase quality.

PubMed

Bækvad-Hansen, Marie; Bybjerg-Grauholm, Jonas; Poulsen, Jesper B; Hansen, Christine S; Hougaard, David M; Hollegaard, Mads V

2017-06-01

The overall aim of this study is to evaluate whole genome amplification of DNA extracted from dried blood spot samples. We wish to explore ways of optimizing the amplification process, while decreasing the amount of input material and inherently the cost. Our primary focus of optimization is on the amount of input material, the amplification reaction volume, the number of replicates and amplification time and temperature. Increasing the quality of the amplified DNA and the subsequent results of array genotyping is a secondary aim of this project. This study is based on DNA extracted from dried blood spot samples. The extracted DNA was subsequently whole genome amplified using the REPLIg kit and genotyped on the PsychArray BeadChip (assessing > 570,000 SNPs genome wide). We used Genome Studio to evaluate the quality of the genotype data by call rates and log R ratios. The whole genome amplification process is robust and does not vary between replicates. Altering amplification time, temperature or number of replicates did not affect our results. We found that spot size i.e. amount of input material could be reduced without compromising the quality of the array genotyping data. We also showed that whole genome amplification reaction volumes can be reduced by a factor of 4, without compromising the DNA quality. Whole genome amplified DNA samples from dried blood spots is well suited for array genotyping and produces robust and reliable genotype data. However, the amplification process introduces additional noise to the data, making detection of structural variants such as copy number variants difficult. With this study, we explore ways of optimizing the amplification protocol in order to reduce noise and increase data quality. We found, that the amplification process was very robust, and that changes in amplification time or temperature did not alter the genotyping calls or quality of the array data. Adding additional replicates of each sample also lead to insignificant changes in the array data. Thus, the amount of noise introduced by the amplification process was consistent regardless of changes made to the amplification protocol. We also explored ways of decreasing material expenditure by reducing the spot size or the amplification reaction volume. The reduction did not affect the quality of the genotyping data.

Adolescents who were born very preterm have decreased brain volumes.

PubMed

Nosarti, Chiara; Al-Asady, Mazin H S; Frangou, Sophia; Stewart, Ann L; Rifkin, Larry; Murray, Robin M

2002-07-01

Infants born very preterm have an increased risk of brain injury. Given the great increase in the number of such infants that are surviving, it is important to establish whether any resultant brain abnormalities persist into adolescence and adult life. We therefore examined in vivo whole brain, grey matter, white matter and hippocampal volumes, ventricular size and grey/white matter ratios in a series of adolescents who had been born very preterm, and an age-matched full-term control group. Structural MRI was carried out on a cohort of 72 adolescents (mean age 15 years) who were born before 33 weeks, and 48 age-matched full-term controls. Brain measurements were made blind to group affiliation using stereological principles. After controlling for gender and height, the very preterm subjects showed a 6.0% decrease in whole brain volume, and an 11.8% decrease in cortical grey matter volume, as well as a 15.6% decrease in right and a 12.1% decrease in left hippocampal volumes; they also had a 42.0% increase in the size of the lateral ventricles. Therefore, individuals who were born very preterm continue to show noticeable decrements in brain volumes and striking increases in lateral ventricular volume into adolescence. The functional significance of these abnormalities merits further investigation.

Carpal tunnel volume changes of the wrist under distraction.

PubMed

Cho, M S; Means, K R; Shrout, J A; Segalman, K A

2008-10-01

This study attempts to determine changes in carpal canal volume with distraction across the wrist. Uniform longitudinal distraction was maintained with two external fixators on the radial and ulnar aspects of the forearm axis of five cadaver specimens. After CT scanning, volume determinations were made at 5 mm increments beginning at the lunocapitate joint to a point 1.5 cm distal to the middle finger carpometacarpal joint. There was a statistically significant decrease of the mean total carpal canal volume from 0 to 4.54 kg of distraction, with no statistically significant decrease from 0 to 2.27 kg or 2.27 to 4.54 kg. The largest decrease occurred at 15 and 20 mm distal to the proximal edge of the transverse carpal ligament corresponding to the level of the hamate hook. Reduction in mean carpal canal volume was 10.2% and 7.5% at these distances, respectively, from 0 to 4.54 kg of distraction. Progressive distraction across the wrist causes a decrease in total carpal canal volume.

Enzymatic lignocellulose hydrolysis: Improved cellulase productivity by insoluble solids recycling

PubMed Central

2013-01-01

Background It is necessary to develop efficient methods to produce renewable fuels from lignocellulosic biomass. One of the main challenges to the industrialization of lignocellulose conversion processes is the large amount of cellulase enzymes used for the hydrolysis of cellulose. One method for decreasing the amount of enzyme used is to recycle the enzymes. In this study, the recycle of enzymes associated with the insoluble solid fraction after the enzymatic hydrolysis of cellulose was investigated for pretreated corn stover under a variety of recycling conditions. Results It was found that a significant amount of cellulase activity could be recovered by recycling the insoluble biomass fraction, and the enzyme dosage could be decreased by 30% to achieve the same glucose yields under the most favorable conditions. Enzyme productivity (g glucose produced/g enzyme applied) increased between 30 and 50% by the recycling, depending on the reaction conditions. While increasing the amount of solids recycled increased process performance, the methods applicability was limited by its positive correlation with increasing total solids concentrations, reaction volumes, and lignin content of the insoluble residue. However, increasing amounts of lignin rich residue during the recycle did not negatively impact glucose yields. Conclusions To take advantage of this effect, the amount of solids recycled should be maximized, based on a given processes ability to deal with higher solids concentrations and volumes. Recycling of enzymes by recycling the insoluble solids fraction was thus shown to be an effective method to decrease enzyme usage, and research should be continued for its industrial application. PMID:23336604

Positron Annihilation Spectroscopy during physical aging of carbon-black filled rubber composites

NASA Astrophysics Data System (ADS)

Jobando, Vincent; Wang, Jingyi; Quarles, C. A.

2004-10-01

We have used positron annihilation spectroscopy to investigate the relaxation behavior of vulcanized and un-vulcanized rubber-carbon black composites. The samples were studied at temperatures above their glassy transitions. Changes in o-Ps intensity and S-parameter are indicative of the structural relaxation process. We have found that at room temperature, both vulcanized and un-vulcanized rubber showed no changes after ageing for about two months. While within the same period, un-vulcanized samples heated at 60^oC and allowed to age at room -temperature showed a decrease in o-Ps intensity and S-parameter. The o-Ps lifetime also decreased after this heat treatment for the un-vulcanized samples while the vulcanized ones remained unchanged. The changes seen were reversible however when we stopped heating the samples. We proposed that heat disordered the system and on cooling, rubber molecules formed more ordered regions, which we interpreted as crystallization. Vulcanized samples remained unchanged. We also found out that free volume decreases during physical deformation of pure rubber, but rubber with carbon black showed a significant rise in free volume. The lifetimes however remained unchanged.

Clinical usefulness of the definitions for defining characteristics of activity intolerance, excess fluid volume and decreased cardiac output in decompensated heart failure: a descriptive exploratory study.

PubMed

de Souza, Vanessa; Zeitoun, Sandra Salloum; Lopes, Camila Takao; de Oliveira, Ana Paula Dias; Lopes, Juliana de Lima; de Barros, Alba Lucia Bottura Leite

2015-09-01

To assess the clinical usefulness of the operational definitions for the defining characteristics of the NANDA International nursing diagnoses, activity intolerance, decreased cardiac output and excess fluid volume, and the concomitant presence of those diagnoses in patients with decompensated heart failure. Content validity of the operational definitions for the defining characteristics of activity intolerance, excess fluid volume and decreased cardiac output have been previously validated by experts. Their clinical usefulness requires clinical validation. This was a descriptive exploratory study. Two expert nurses independently assessed 25 patients with decompensated heart failure for the presence or absence of 29 defining characteristics. Interrater reliability was analysed using the Kappa coefficient as a measure of clinical usefulness. The Fisher's exact test was used to test the association of the defining characteristics of activity intolerance and excess fluid volume in the presence of decreased cardiac output, and the correlation between the three diagnoses. Assessments regarding the presence of all defining characteristics reached 100% agreement, except with anxiety. Five defining characteristics of excess fluid volume were significantly associated with the presence of decreased cardiac output. Concomitant presence of the three diagnoses occurred in 80% of the patients. However, there was no significant correlation between the three diagnoses. The operational definitions for the diagnoses had strong interrater reliability, therefore they were considered clinically useful. Only five defining characteristics were representative of the association between excess fluid volume and decreased cardiac output. Therefore, excess fluid volume is related to decreased cardiac output, although these diagnoses are not necessarily associated with activity intolerance. The operational definitions may favour early recognition of the sequence of responses to decompensation, guiding the choice of common interventions to improve or resolve excess fluid volume and decreased cardiac output. © 2015 John Wiley & Sons Ltd.

Application of advanced diffraction based optical metrology overlay capabilities for high-volume manufacturing

NASA Astrophysics Data System (ADS)

Chen, Kai-Hsiung; Huang, Guo-Tsai; Hsieh, Hung-Chih; Ni, Wei-Feng; Chuang, S. M.; Chuang, T. K.; Ke, Chih-Ming; Huang, Jacky; Rao, Shiuan-An; Cumurcu Gysen, Aysegul; d'Alfonso, Maxime; Yueh, Jenny; Izikson, Pavel; Soco, Aileen; Wu, Jon; Nooitgedagt, Tjitte; Ottens, Jeroen; Kim, Yong Ho; Ebert, Martin

2017-03-01

On-product overlay requirements are becoming more challenging with every next technology node due to the continued decrease of the device dimensions and process tolerances. Therefore, current and future technology nodes require demanding metrology capabilities such as target designs that are robust towards process variations and high overlay measurement density (e.g. for higher order process corrections) to enable advanced process control solutions. The impact of advanced control solutions based on YieldStar overlay data is being presented in this paper. Multi patterning techniques are applied for critical layers and leading to additional overlay measurement demands. The use of 1D process steps results in the need of overlay measurements relative to more than one layer. Dealing with the increased number of overlay measurements while keeping the high measurement density and metrology accuracy at the same time presents a challenge for high volume manufacturing (HVM). These challenges are addressed by the capability to measure multi-layer targets with the recently introduced YieldStar metrology tool, YS350. On-product overlay results of such multi-layers and standard targets are presented including measurement stability performance.

Mechanical and electrical anisotropy in Mimosa pudica pulvini

PubMed Central

Foster, Justin C; Baker, Kara D; Markin, Vladislav S

2010-01-01

Thigmonastic or seismonastic movements in Mimosa pudica, such as the response to touch, appear to be regulated by electrical, hydrodynamical and chemical signal transduction. The pulvinus of Mimosa pudica shows elastic properties, and we found that electrically or mechanically induced movements of the petiole were accompanied by a change of the pulvinus shape. As the petiole falls, the volume of the lower part of the pulvinus decreases and the volume of the upper part increases due to the redistribution of water between the upper and lower parts of the pulvinus. This hydroelastic process is reversible. During the relaxation of the petiole, the volume of the lower part of the pulvinus increases and the volume of the upper part decreases. Redistribution of ions between the upper and lower parts of a pulvinus causes fast transport of water through aquaporins and causes a fast change in the volume of the motor cells. Here, the biologically closed electrochemical circuits in electrically and mechanically anisotropic pulvini of Mimosa pudica are analyzed using the charged capacitor method for electrostimulation at different voltages. Changing the polarity of electrodes leads to a strong rectification effect in a pulvinus and to different kinetics of a capacitor discharge if the applied initial voltage is 0.5 V or higher. The electrical properties of Mimosa pudica's pulvini were investigated and the equivalent electrical circuit within the pulvinus was proposed to explain the experimental data. The detailed mechanism of seismonastic movements in Mimosa pudica is discussed. PMID:20855975

Mechanical and electrical anisotropy in Mimosa pudica pulvini.

PubMed

Volkov, Alexander G; Foster, Justin C; Baker, Kara D; Markin, Vladislav S

2010-10-01

Thigmonastic or seismonastic movements in Mimosa pudica, such as the response to touch, appear to be regulated by electrical, hydrodynamical, and chemical signal transduction. The pulvinus of Mimosa pudica shows elastic properties, and we found that electrically or mechanically induced movements of the petiole were accompanied by a change of the pulvinus shape. As the petiole falls, the volume of the lower part of the pulvinus decreases and the volume of the upper part increases due to the redistribution of water between the upper and lower parts of the pulvinus. This hydroelastic process is reversible. During the relaxation of the petiole, the volume of the lower part of the pulvinus increases and the volume of the upper part decreases. Redistribution of ions between the upper and lower parts of a pulvinus causes fast transport of water through aquaporins and causes a fast change in the volume of the motor cells. Here, the biologically closed electrochemical circuits in electrically and mechanically anisotropic pulvini of Mimosa pudica are analyzed using the charged capacitor method for electrostimulation at different voltages. Changing the polarity of electrodes leads to a strong rectification effect in a pulvinus and to different kinetics of a capacitor discharge if the applied initial voltage is 0.5 V or higher. The electrical properties of Mimosa pudica's pulvini were investigated and the equivalent electrical circuit within the pulvinus was proposed to explain the experimental data. The detailed mechanism of seismonastic movements in Mimosa pudica is discussed. © 2010 Landes Bioscience

Patient-reported ejaculatory function and satisfaction in men with lower urinary tract symptoms/benign prostatic hyperplasia.

PubMed

Cho, Min Chul; Kim, Jung Kwon; Song, Sang Hoon; Cho, Sung Yong; Lee, Sang Wook; Kim, Soo Woong; Paick, Jae-Seung

2018-01-01

This study aimed to investigate perceived ejaculatory function/satisfaction before treatment for lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH) and to identify associations between specific categories of ejaculatory dysfunctions (EjDs) and LUTS. A total of 1574 treatment-naïve men with LUTS/BPH were included in this study. All patients underwent routine evaluation for LUTS/BPH including the International Index of Erectile Function and a 5-item questionnaire developed to assess ejaculatory volume/force/pain/satisfaction/latency time. Patients who had sexual intercourse over the past 4 weeks were classified as sexually active group. A total of 783 patients were categorized as sexually active group. Decreased ejaculatory volume and force were reported by 53.4% and 55.7% of 783 sexually active men, respectively. There was a strong correlation between ejaculatory volume and force. Ejaculatory pain/discomfort, premature ejaculation (PE), and delayed ejaculation (DE) were reported in 41.0%, 16.3%, and 41.4% of the patients, respectively. Over 40.0% of men without decreased ejaculation volume/force were satisfied with ejaculatory function, whereas approximately 6.0% of men with decreased volume/force were satisfied with ejaculatory function. About 30.0% of men with decreased volume/force had orgasmic dysfunction, while approximately 10.0% of men without decreased volume/force did. Decreased ejaculatory volume or force was associated with LUTS severity after adjusting for other influential factors including testosterone level, erectile function, and prostate size on ultrasonography, but PE or DE or ejaculatory pain/discomfort was not. In conclusion, a considerable portion of men with LUTS/BPH appear to have a variety of EjDs. Ejaculatory volume/force and satisfaction/orgasm do not always appear to be concordant. Ejaculatory volume or force is independently associated with LUTS severity, whereas PE or DE or ejaculatory pain/discomfort is not.

Effects of Early Life Stress on Depression, Cognitive Performance, and Brain Morphology

PubMed Central

Saleh, Ayman; Potter, Guy G.; McQuoid, Douglas R.; Boyd, Brian; Turner, Rachel; MacFall, James R; Taylor, Warren D.

2016-01-01

Background Childhood early life stress (ELS) increases risk of adulthood Major Depressive Disorder (MDD) and is associated with altered brain structure and function. It is unclear whether specific ELSs affect depression risk, cognitive function and brain structure. Methods This cross-sectional study included 64 antidepressant-free depressed and 65 never depressed individuals. Both groups reported a range of ELSs on the Early Life Stress Questionnaire, completed neuropsychological testing and 3T MRI. Neuropsychological testing assessed domains of episodic memory, working memory, processing speed and executive function. MRI measures included cortical thickness and regional gray matter volumes, with a priori focus on cingulate cortex, orbitofrontal cortex (OFC), amygdala, caudate and hippocampus. Results Of 19 ELSs, only emotional abuse, sexual abuse and severe family conflict independently predicted adulthood MDD diagnosis. The effect of total ELS score differed between groups. Greater ELS exposure was associated with slower processing speed and smaller OFC volumes in depressed subjects, but faster speed and larger volumes in nondepressed subjects. In contrast, exposure to ELSs predictive of depression had similar effects in both diagnostic groups. Individuals reporting predictive ELSs exhibited poorer processing speed and working memory performance, smaller volumes of the lateral OFC and caudate, and decreased cortical thickness in multiple areas including the insula bilaterally. Predictive ELS exposure was also associated with smaller left hippocampal volume in depressed subjects. Conclusion Findings suggest an association between childhood trauma exposure and adulthood cognitive function and brain structure. These relationships appear to differ between individuals who do and do not develop depression. PMID:27682320

The Short-Term Effect of Weight Loss Surgery on Volumetric Breast Density and Fibroglandular Volume.

PubMed

Vohra, Nasreen A; Kachare, Swapnil D; Vos, Paul; Schroeder, Bruce F; Schuth, Olga; Suttle, Dylan; Fitzgerald, Timothy L; Wong, Jan H; Verbanac, Kathryn M

2017-04-01

Obesity and breast density are both associated with an increased risk of breast cancer and are potentially modifiable. Weight loss surgery (WLS) causes a significant reduction in the amount of body fat and a decrease in breast cancer risk. The effect of WLS on breast density and its components has not been documented. Here, we analyze the impact of WLS on volumetric breast density (VBD) and on each of its components (fibroglandular volume and breast volume) by using three-dimensional methods. Fibroglandular volume, breast volume, and their ratio, the VBD, were calculated from mammograms before and after WLS by using Volpara™ automated software. For the 80 women included, average body mass index decreased from 46.0 ± 7.22 to 33.7 ± 7.06 kg/m 2 . Mammograms were performed on average 11.6 ± 9.4 months before and 10.1 ± 7 months after WLS. There was a significant reduction in average breast volume (39.4 % decrease) and average fibroglandular volume (15.5 % decrease), and thus, the average VBD increased from 5.15 to 7.87 % (p < 1 × 10 -9 ) after WLS. When stratified by menopausal status and diabetic status, VBD increased significantly in all groups but only perimenopausal and postmenopausal women and non-diabetics experienced a significant reduction in fibroglandular volume. Breast volume and fibroglandular volume decreased, and VBD increased following WLS, with the most significant change observed in postmenopausal women and non-diabetics. Further studies are warranted to determine how physical and biological alterations in breast density components after WLS may impact breast cancer risk.

The origin of coercivity decrease in fine grained Nd-Fe-B sintered magnets

NASA Astrophysics Data System (ADS)

Li, W. F.; Ohkubo, T.; Hono, K.; Sagawa, M.

2009-04-01

Microstructures of fine grained Nd-Fe-B sintered magnets that were produced by the pressless process were investigated to understand the origin of the sudden coercivity decrease below a certain grain size. The intrinsic coercivity is inversely proportional to ln D2 with the highest coercivity of 17 kOe at D˜4.5 μm, below which the coercivity drops as the grain size decreases. We found that the degradation of the coercivity of the magnet with a grain size of 3 μm was mainly caused by the inhomogeneous distribution of fcc-Nd oxide whose volume fraction increased with respect to the dhcp Nd-rich phase.

Defect evolution and impurity migration in Na-implanted ZnO

NASA Astrophysics Data System (ADS)

Neuvonen, Pekka T.; Vines, Lasse; Venkatachalapathy, Vishnukanthan; Zubiaga, Asier; Tuomisto, Filip; Hallén, Anders; Svensson, Bengt G.; Kuznetsov, Andrej Yu.

2011-11-01

Secondary ion mass spectrometry (SIMS) and positron annihilation spectroscopy (PAS) have been applied to study impurity migration and open volume defect evolution in Na+ implanted hydrothermally grown ZnO samples. In contrast to most other elements, the presence of Na tends to decrease the concentration of open volume defects upon annealing and for temperatures above 600∘C, Na exhibits trap-limited diffusion correlating with the concentration of Li. A dominating trap for the migrating Na atoms is most likely Li residing on Zn site, but a systematic analysis of the data suggests that zinc vacancies also play an important role in the trapping process.

Does lake size matter? Combining morphology and process modeling to examine the contribution of lake classes to population-scale processes

USGS Publications Warehouse

Winslow, Luke A.; Read, Jordan S.; Hanson, Paul C.; Stanley, Emily H.

2014-01-01

With lake abundances in the thousands to millions, creating an intuitive understanding of the distribution of morphology and processes in lakes is challenging. To improve researchers’ understanding of large-scale lake processes, we developed a parsimonious mathematical model based on the Pareto distribution to describe the distribution of lake morphology (area, perimeter and volume). While debate continues over which mathematical representation best fits any one distribution of lake morphometric characteristics, we recognize the need for a simple, flexible model to advance understanding of how the interaction between morphometry and function dictates scaling across large populations of lakes. These models make clear the relative contribution of lakes to the total amount of lake surface area, volume, and perimeter. They also highlight the critical thresholds at which total perimeter, area and volume would be evenly distributed across lake size-classes have Pareto slopes of 0.63, 1 and 1.12, respectively. These models of morphology can be used in combination with models of process to create overarching “lake population” level models of process. To illustrate this potential, we combine the model of surface area distribution with a model of carbon mass accumulation rate. We found that even if smaller lakes contribute relatively less to total surface area than larger lakes, the increasing carbon accumulation rate with decreasing lake size is strong enough to bias the distribution of carbon mass accumulation towards smaller lakes. This analytical framework provides a relatively simple approach to upscaling morphology and process that is easily generalizable to other ecosystem processes.

Pentagastrin-induced hemoconcentration in healthy volunteers and patients with panic disorder: effect of pretreatment with ethinyl estradiol.

PubMed

Le Melledo, Jean Michel; Perez-Parada, Jorge; Morrow, Jarret; Bellavance, Francois; Lara, Nathalie; Jahandar, Farideh; Granger, Robert; Tait, Glendon; McManus, Karen

2011-01-01

Panic disorder has been associated with both an increased risk of coronary events as well as an increased risk of stroke. Hemoconcentration, with both a decrease in plasma volume and an increase in plasma viscosity, is a possible contributor to the risk of acute ischemic events. Our objectives were to demonstrate the process of hemoconcentration in response to induced panic symptoms and to assess the effect of pretreatment with ethinyl estradiol on panic-induced hemoconcentration. Fifteen male patients with panic disorder and 10 male healthy volunteers were included in a double-blind cross-over placebo-controlled design consisting of two injections of pentagastrin following randomized pretreatment with placebo and ethinyl estradiol. Plasma levels of hematocrit and hemoglobin were assessed at baseline and post-injections, and used to calculate an indirect estimation of the change in plasma volume. Pentagastrin-induced panic symptoms were associated with a mean decrease in plasma volume of 4.8% in the placebo pretreatment condition. Pretreatment with ethinyl estradiol attenuated this effect. The acute hemoconcentration observed in relation to pentagastrin-induced panic symptoms may be relevant to the increased risk of stroke and acute coronary events found in patients with panic disorder.

Strong ion exchange in centrifugal partition extraction (SIX-CPE): effect of partition cell design and dimensions on purification process efficiency.

PubMed

Hamzaoui, Mahmoud; Hubert, Jane; Reynaud, Romain; Marchal, Luc; Foucault, Alain; Renault, Jean-Hugues

2012-07-20

The aim of this article was to evaluate the influence of the column design of a hydrostatic support-free liquid-liquid chromatography device on the process efficiency when the strong ion-exchange (SIX) development mode is used. The purification of p-hydroxybenzylglucosinolate (sinalbin) from a crude aqueous extract of white mustard seeds (Sinapis alba L.) was achieved on two types of devices: a centrifugal partition chromatograph (CPC) and a centrifugal partition extractor (CPE). They differ in the number, volume and geometry of their partition cells. The SIX-CPE process was evaluated in terms of productivity and sinalbin purification capability as compared to previously optimized SIX-CPC protocols that were carried out on columns of 200 mL and 5700 mL inner volume, respectively. The objective was to determine whether the decrease in partition cell number, the increase in their volume and the use of a "twin cell" design would induce a significant increase in productivity by applying higher mobile phase flow rate while maintaining a constant separation quality. 4.6g of sinalbin (92% recovery) were isolated from 25 g of a crude white mustard seed extract, in only 32 min and with a purity of 94.7%, thus corresponding to a productivity of 28 g per hour and per liter of column volume (g/h/LV(c)). Therefore, the SIX-CPE process demonstrates promising industrial technology transfer perspectives for the large-scale isolation of ionized natural products. Copyright © 2012 Elsevier B.V. All rights reserved.

Effect of Lean Processes on Surgical Wait Times and Efficiency in a Tertiary Care Veterans Affairs Medical Center.

PubMed

Valsangkar, Nakul P; Eppstein, Andrew C; Lawson, Rick A; Taylor, Amber N

2017-01-01

There are an increasing number of veterans in the United States, and the current delay and wait times prevent Veterans Affairs institutions from fully meeting the needs of current and former service members. Concrete strategies to improve throughput at these facilities have been sparse. To identify whether lean processes can be used to improve wait times for surgical procedures in Veterans Affairs hospitals. Databases in the Veterans Integrated Service Network 11 Data Warehouse, Veterans Health Administration Support Service Center, and Veterans Information Systems and Technology Architecture/Dynamic Host Configuration Protocol were queried to assess changes in wait times for elective general surgical procedures and clinical volume before, during, and after implementation of lean processes over 3 fiscal years (FYs) at a tertiary care Veterans Affairs medical center. All patients evaluated by the general surgery department through outpatient clinics, clinical video teleconferencing, and e-consultations from October 2011 through September 2014 were included. Patients evaluated through the emergency department or as inpatient consults were excluded. The surgery service and systems redesign service held a value stream analysis in FY 2013, culminating in multiple rapid process improvement workshops. Multidisciplinary teams identified systemic inefficiencies and strategies to improve interdepartmental and patient communication to reduce canceled consultations and cases, diagnostic rework, and no-shows. High-priority triage with enhanced operating room flexibility was instituted to reduce scheduling wait times. General surgery department pilot projects were then implemented mid-FY 2013. Planned outcome measures included wait time, clinic and telehealth volume, number of no-shows, and operative volume. Paired t tests were used to identify differences in outcome measures after the institution of reforms. Following rapid process improvement workshop project rollouts, mean (SD) patient wait times for elective general surgical procedures decreased from 33.4 (8.3) days in FY 2012 to 26.0 (9.5) days in FY 2013 (P = .02). In FY 2014, mean (SD) wait times were half the value of the previous FY at 12.0 (2.1) days (P = .07). This was a 3-fold decrease from wait times in FY 2012 (P = .02). Operative volume increased from 931 patients in FY 2012 to 1090 in FY 2013 and 1072 in FY 2014. Combined clinic, telehealth, and e-consultation encounters increased from 3131 in FY 2012 to 3460 in FY 2013 and 3517 in FY 2014, while the number of no-shows decreased from 366 in FY 2012 to 227 in FY 2014 (P = .02). Improvement in the overall surgical patient experience can stem from multidisciplinary collaboration among systems redesign personnel, clinicians, and surgical staff to reduce systemic inefficiencies. Monitoring and follow-up of system efficiency measures and the employment of lean practices and process improvements can have positive short- and long-term effects on wait times, clinical throughput, and patient care and satisfaction.

Investigation of mechanical properties for open cellular structure CoCrMo alloy fabricated by selective laser melting process

NASA Astrophysics Data System (ADS)

Azidin, A.; Taib, Z. A. M.; Harun, W. S. W.; Che Ghani, S. A.; Faisae, M. F.; Omar, M. A.; Ramli, H.

2015-12-01

Orthodontic implants have been a major focus through mechanical and biological performance in advance to fabricate shape of complex anatomical. Designing the part with a complex mechanism is one of the challenging process and addition to achieve the balance and desired mechanical performance brought to the right manufacture technique to fabricate. Metal additive manufacturing (MAM) is brought forward to the newest fabrication technology in this field. In this study, selective laser melting (SLM) process was utilized on a medical grade cobalt-chrome molybdenum (CoCrMo) alloy. The work has focused on mechanical properties of the CoCrMo open cellular structures samples with 60%, 70%, and 80% designed volume porosity that could potentially emulate the properties of human bone. It was observed that hardness values decreased as the soaking time increases except for bottom face. For compression test, 60% designed volume porosity demonstrated highest ultimate compressive strength compared to 70% and 80%.

Brain activity changes in cognitive networks in relapsing-remitting multiple sclerosis - insights from a longitudinal FMRI study.

PubMed

Loitfelder, Marisa; Fazekas, Franz; Koschutnig, Karl; Fuchs, Siegrid; Petrovic, Katja; Ropele, Stefan; Pichler, Alexander; Jehna, Margit; Langkammer, Christian; Schmidt, Reinhold; Neuper, Christa; Enzinger, Christian

2014-01-01

Extrapolations from previous cross-sectional fMRI studies suggest cerebral functional changes with progression of Multiple Sclerosis (MS), but longitudinal studies are scarce. We assessed brain activation changes over time in MS patients using a cognitive fMRI paradigm and examined correlations with clinical and cognitive status and brain morphology. 13 MS patients and 15 healthy controls (HC) underwent MRI including fMRI (go/no-go task), neurological and neuropsychological exams at baseline (BL) and follow-up (FU; minimum 12, median 20 months). We assessed estimates of and changes in fMRI activation, total brain and subcortical grey matter volumes, cortical thickness, and T2-lesion load. Bland-Altman (BA) plots served to assess fMRI signal variability. Cognitive and disability levels remained largely stable in the patients. With the fMRI task, both at BL and FU, patients compared to HC showed increased activation in the insular cortex, precuneus, cerebellum, posterior cingulate cortex, and occipital cortex. At BL, patients vs. HC also had lower caudate nucleus, thalamus and putamen volumes. Over time, patients (but not HC) demonstrated fMRI activity increments in the left inferior parietal lobule. These correlated with worse single-digit-modality test (SDMT) performance. BA-plots attested to reproducibility of the fMRI task. In the patients, the right caudate nucleus decreased in volume which again correlated with worsening SDMT performance. Given preserved cognitive performance, the increased activation at BL in the patients may be viewed as largely adaptive. In contrast, the negative correlation with SDMT performance suggests increasing parietal activation over time to be maladaptive. Several areas with purported relevance for cognition showed decreased volumes at BL and right caudate nucleus volume decline correlated with decreasing SDMT performance. This highlights the dynamics of functional changes and the strategic importance of specific brain areas for cognitive processes in MS.

Diurnal Changes in Volume and Specific Tissue Weight of Crassulacean Acid Metabolism Plants 1

PubMed Central

Chen, Sheng-Shu; Black, Clanton C.

1983-01-01

The diurnal variations in volume and in specific weight were determined for green stems and leaves of Crassulacen acid metabolism (CAM) plants. Volume changes were measured by a water displacement method. Diurnal variations occurred in the volume of green CAM tissues. Their volume increased early in the light period reaching a maximum about mid-day, then the volume decreased to a minimum near midnight. The maximum volume increase each day was about 2.7% of the total volume. Control leaves of C3 and C4 plants exhibited reverse diurnal volume changes of 0.2 to 0.4%. The hypothesis is presented and supported that green CAM tissues should exhibit a diurnal increase in volume due to the increase of internal gas pressure from CO2 and O2 when their stomata are closed. Conversely, the volume should decrease when the gas pressure is decreased. The second hypothesis presented and supported was that the specific weight (milligrams of dry weight per square centimeter of green surface area) of green CAM tissues should increase at night due to the net fixation of CO2. Green CAM tissues increased their specific weight at night in contrast to control C3 and C4 leaves which decreased their specific weight at night. With Kalanchoë daigremontiana leaves, the calculated increase in specific leaf weight at night based on estimates of carbohydrate available for net CO2 fixation was near 6% and the measured increase in specific leaf weight was 6%. Diurnal measurements of CAM tissue water content were neither coincident nor reciprocal with their diurnal patterns of either volume or specific weight changes. PMID:16662833

Estimating the impact of somatic cell count on the value of milk utilising parameters obtained from the published literature.

PubMed

Geary, Una; Lopez-Villalobos, Nicolas; O'Brien, Bernadette; Garrick, Dorian J; Shalloo, Laurence

2014-05-01

The impact of mastitis on milk value per litre independent of the effect of mastitis on milk volume, was quantified for Ireland using a meta-analysis and a processing sector model. Changes in raw milk composition, cheese processing and composition associated with increased bulk milk somatic cell count (BMSCC) were incorporated into the model. Processing costs and market values were representative of current industry values. It was assumed that as BMSCC increased (i) milk fat and milk protein increased and milk lactose decreased, (ii) fat and protein recoveries decreased, (iii) cheese protein decreased and cheese moisture increased. Five BMSCC categories were examined from ⩽100 000 to >400 000 cells/ml. The analysis showed that as BMSCC increased the production quantities reduced. An increase in BMSCC from 100 000 to >400 000 cells/ml saw a reduction in net revenue of 3·2% per annum (€51·3 million) which corresponded to a reduction in the value of raw milk of €0·0096 cents/l.

Effects of isotretinoin on the platelet counts and the mean platelet volume in patients with acne vulgaris.

PubMed

Ataseven, Arzu; Ugur Bilgin, Aynur

2014-01-01

Aim. The aim of this study was to evaluate the platelet counts and the mean platelet volume in patients who received isotretinoin for the treatment of acne vulgaris. Method. A total of 110 patients were included in this retrospective study. Complete blood count parameters were recorded prior to and three-months following the treatment. Results. Both platelet counts and the mean platelet volume were significantly decreased following the treatment. No significant differences were noted on the levels of hemoglobin, hematocrit, and white blood cell count. Conclusion. Platelet counts and mean platelet volume significantly decreased following isotretinoin treatment. Since the decrease of platelet counts and the mean platelet volume was seen concomitantly, it is concluded that the effect of isotretinoin was through the suppression of bone marrow.

Food habits of Nyctinomops macrotis at a maternity roost in New Mexico, as indicated by analysis of guano

USGS Publications Warehouse

Sparks, D.W.; Valdez, E.W.

2003-01-01

We examined 56 fecal pellets from under a maternity colony of big free-tailed bats (Nyctinomops macrotis) in the Jemez Mountains of northern New Mexico. The most important food items, listed in order of decreasing percent volume, were Cicadellidae, leafhoppers (26.7% volume, 58.9% frequency); Ichneumonidae, Ichneumon wasps (19.3% volume, 35.7% frequency); and Lepidoptera, moths (17.2% volume, 82.1% frequency). Overall, the most important orders as prey consumed, listed by decreasing percent volume, were Homoptera (27.6% volume, 62.5% frequency), Hymenoptera (19.5% volume, 37.5% frequency), Lepidoptera (17.2% volume, 82.1% frequency), Hemiptera (11.7% volume, 37.5% frequency), and Diptera (10.6% volume, 50.0% frequency). Our study documents an unusually varied diet, as previous studies indicated that these bats fed almost exclusively on moths.

Gray matter alteration in isolated congenital anosmia patient: a voxel-based morphometry study.

PubMed

Yao, Linyin; Yi, Xiaoli; Wei, Yongxiang

2013-09-01

Decreased volume of gray matter (GM) was observed in olfactory loss in patients with neurodegenerative disorder. However, GM volume has not yet been investigated in isolated congenital anosmia (ICA) people. We herewith investigated the volume change of gray matter of an ICA boy by morphometric analysis of magnetic resonance images (voxel-based morphometry), and compared with that of 20 age-matched healthy controls. ICA boy presented a significant decrease in GM volume in the orbitofrontal cortex, anterior cingulate cortex, middle cingulate cortex, thalamus, insular cortex, cerebellum, precuneus, gyrus rectus, subcallosal gyrus, middle temporal gyrus, fusiform gyrus and piriform cortex. No significant GM volume increase was detected in other brain areas. The pattern of GM atrophy was similar as previous literature reported. Our results identified similar GM volume alterations regardless of the causes of olfactory impairment. Decreased GM volume was not only shown in olfactory bulbs, olfactory tracts and olfactory sulcus, also in primary olfactory cortex and the secondary cerebral olfactory areas in ICA people. This is the first study to evaluate GM volume alterations in ICA people.

Characterizing Volumetric Strain at Brady Hot Springs, Nevada, USA Using Geodetic Data, Numerical Models, and Prior Information

NASA Astrophysics Data System (ADS)

Reinisch, E. C.; Feigl, K. L.; Cardiff, M. A.; Morency, C.; Kreemer, C.; Akerley, J.

2017-12-01

Time-dependent deformation has been observed at Brady Hot Springs using data from the Global Positioning System (GPS) and interferometric synthetic aperture radar (InSAR) [e.g., Ali et al. 2016, http://dx.doi.org/10.1016/j.geothermics.2016.01.008]. We seek to determine the geophysical process governing the observed subsidence. As two end-member hypotheses, we consider thermal contraction and a decrease in pore fluid pressure. A decrease in temperature would cause contraction in the subsurface and subsidence at the surface. A decrease in pore fluid pressure would allow the volume of pores to shrink and also produce subsidence. To simulate these processes, we use a dislocation model that assumes uniform elastic properties in a half space [Okada, 1985]. The parameterization consists of many cubic volume elements (voxels), each of which contracts by closing its three mutually orthogonal bisecting square surfaces. Then we use linear inversion to solve for volumetric strain in each voxel given a measurement of range change. To differentiate between the two possible hypotheses, we use a Bayesian framework with geostatistical prior information. We perform inversion using each prior to decide if one leads to a more geophysically reasonable interpretation than the other. This work is part of a project entitled "Poroelastic Tomography by Adjoint Inverse Modeling of Data from Seismology, Geodesy, and Hydrology" and is supported by the Geothermal Technology Office of the U.S. Department of Energy [DE-EE0006760].

Effects of adrenergic stimulation on ventilation in man

PubMed Central

Heistad, Donald D.; Wheeler, Robert C.; Mark, Allyn L.; Schmid, Phillip G.; Abboud, Francois M.

1972-01-01

The mechanism by which catecholamines affect ventilation in man is not known. Ventilatory responses to catecholamines were observed in normal subjects before and after adrenergic receptor blockade. Intravenous infusions of norepinephrine and isoproterenol caused significant increases in minute volume and decreases in end-tidal PCo2 which were blocked by the administration of propranolol, a beta adrenergic receptor blocker. The hyperventilatory response to hypoxia was not altered by propranolol. Intravenous infusion of phenylephrine caused a small but significant decrease in minute volume which was antagonized by phentolamine, an alpha adrenergic receptor blocker. Angiotensin, a nonadrenergic pressor agent, also decreased minute volume significantly. 100% oxygen was administered to suppress arterial chemoreceptors. Increases in minute volume and decreases in arterial PCo2 in response to norepinephrine and isoproterenol were blocked by breathing 100% oxygen. The decrease in minute volume during phenylephrine was not altered by 100% oxygen. The results indicate that: (a) beta adrenergic receptors mediate the hyperventilatory response to norepinephrine and isoproterenol but not to hypoxia. (b) the pressor agents phenylephrine and angiotensin decrease ventilation, and (c) suppression of chemoreceptors blocks the ventilatory response to norepinephrine and isoproterenol but not to phenylephrine. Implications concerning the interaction of adrenergic receptors and chemoreceptors with respect to the hyperventilatory response to catecholamines are discussed. PMID:4336940

Temporal processing and adaptation in the songbird auditory forebrain.

PubMed

Nagel, Katherine I; Doupe, Allison J

2006-09-21

Songbird auditory neurons must encode the dynamics of natural sounds at many volumes. We investigated how neural coding depends on the distribution of stimulus intensities. Using reverse-correlation, we modeled responses to amplitude-modulated sounds as the output of a linear filter and a nonlinear gain function, then asked how filters and nonlinearities depend on the stimulus mean and variance. Filter shape depended strongly on mean amplitude (volume): at low mean, most neurons integrated sound over many milliseconds, while at high mean, neurons responded more to local changes in amplitude. Increasing the variance (contrast) of amplitude modulations had less effect on filter shape but decreased the gain of firing in most cells. Both filter and gain changes occurred rapidly after a change in statistics, suggesting that they represent nonlinearities in processing. These changes may permit neurons to signal effectively over a wider dynamic range and are reminiscent of findings in other sensory systems.

Predictive modeling of multicellular structure formation by using Cellular Particle Dynamics simulations

NASA Astrophysics Data System (ADS)

McCune, Matthew; Shafiee, Ashkan; Forgacs, Gabor; Kosztin, Ioan

2014-03-01

Cellular Particle Dynamics (CPD) is an effective computational method for describing and predicting the time evolution of biomechanical relaxation processes of multicellular systems. A typical example is the fusion of spheroidal bioink particles during post bioprinting structure formation. In CPD cells are modeled as an ensemble of cellular particles (CPs) that interact via short-range contact interactions, characterized by an attractive (adhesive interaction) and a repulsive (excluded volume interaction) component. The time evolution of the spatial conformation of the multicellular system is determined by following the trajectories of all CPs through integration of their equations of motion. CPD was successfully applied to describe and predict the fusion of 3D tissue construct involving identical spherical aggregates. Here, we demonstrate that CPD can also predict tissue formation involving uneven spherical aggregates whose volumes decrease during the fusion process. Work supported by NSF [PHY-0957914]. Computer time provided by the University of Missouri Bioinformatics Consortium.

Preliminary report on macroscopic age changes in the human prosencephalon. A stereologic investigation.

PubMed

Eggers, R; Haug, H; Fischer, D

1984-01-01

The studies here reported were performed on the prosencephalons of 12 human brains between 37 and 86 years of age having no signs of neuropathological alteration. The evaluation was carried out on serial frontal sections with a mean thickness of 5 mm with stereological point counting procedures for volume and surface area. The results were mainly given in relative values since the range of variation is very high and the sample small. The aging process was evaluated with the aid of a linear regression function. The stereological investigation regarding the absolute values of volume and surface area (border face) of the macroscopical brain parts show a high interindividual variability. However, the relative volume of brain parts shows only small variations. Changes during aging could consequently only be revealed with the help of the relative values. The relative volumes and surface areas of the frontal lobe and the prosencephalic ganglia decrease with aging, while the parieto-occipital lobe and the striate cortex increase. However, if we refer these relative increases to the absolute decrease of brain volume, corresponding changes cannot be found in the parieto-occipital lobe until old age. The shrinkage of the frontal lobe, of the centrum semiovale and of the prosencephalic ganglia exceeds 10%. In the grays it is probably accompanied by a loss of neurons. The relative sizes of the surface area do not change significantly during aging with exception of the frontal cortex. The thickness of the cortex remains probably constant. The size of lateral ventricles increases with aging.

Ionic imbalance, in addition to molecular crowding, abates cytoskeletal dynamics and vesicle motility during hypertonic stress

PubMed Central

Nunes, Paula; Roth, Isabelle; Meda, Paolo; Féraille, Eric; Brown, Dennis; Hasler, Udo

2015-01-01

Cell volume homeostasis is vital for the maintenance of optimal protein density and cellular function. Numerous mammalian cell types are routinely exposed to acute hypertonic challenge and shrink. Molecular crowding modifies biochemical reaction rates and decreases macromolecule diffusion. Cell volume is restored rapidly by ion influx but at the expense of elevated intracellular sodium and chloride levels that persist long after challenge. Although recent studies have highlighted the role of molecular crowding on the effects of hypertonicity, the effects of ionic imbalance on cellular trafficking dynamics in living cells are largely unexplored. By tracking distinct fluorescently labeled endosome/vesicle populations by live-cell imaging, we show that vesicle motility is reduced dramatically in a variety of cell types at the onset of hypertonic challenge. Live-cell imaging of actin and tubulin revealed similar arrested microfilament motility upon challenge. Vesicle motility recovered long after cell volume, a process that required functional regulatory volume increase and was accelerated by a return of extracellular osmolality to isosmotic levels. This delay suggests that, although volume-induced molecular crowding contributes to trafficking defects, it alone cannot explain the observed effects. Using fluorescent indicators and FRET-based probes, we found that intracellular ATP abundance and mitochondrial potential were reduced by hypertonicity and recovered after longer periods of time. Similar to the effects of osmotic challenge, isovolumetric elevation of intracellular chloride concentration by ionophores transiently decreased ATP production by mitochondria and abated microfilament and vesicle motility. These data illustrate how perturbed ionic balance, in addition to molecular crowding, affects membrane trafficking. PMID:26045497

Does Preinterventional Flat-Panel Computer Tomography Pooled Blood Volume Mapping Predict Final Infarct Volume After Mechanical Thrombectomy in Acute Cerebral Artery Occlusion?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagner, Marlies, E-mail: marlies.wagner@kgu.de; Kyriakou, Yiannis, E-mail: yiannis.kyriakou@siemens.com; Mesnil de Rochemont, Richard du, E-mail: mesnil@em.uni-frankfurt.de

2013-08-01

PurposeDecreased cerebral blood volume is known to be a predictor for final infarct volume in acute cerebral artery occlusion. To evaluate the predictability of final infarct volume in patients with acute occlusion of the middle cerebral artery (MCA) or the distal internal carotid artery (ICA) and successful endovascular recanalization, pooled blood volume (PBV) was measured using flat-panel detector computed tomography (FPD CT).Materials and MethodsTwenty patients with acute unilateral occlusion of the MCA or distal ACI without demarcated infarction, as proven by CT at admission, and successful Thrombolysis in cerebral infarction score (TICI 2b or 3) endovascular thrombectomy were included. Cerebralmore » PBV maps were acquired from each patient immediately before endovascular thrombectomy. Twenty-four hours after recanalization, each patient underwent multislice CT to visualize final infarct volume. Extent of the areas of decreased PBV was compared with the final infarct volume proven by follow-up CT the next day.ResultsIn 15 of 20 patients, areas of distinct PBV decrease corresponded to final infarct volume. In 5 patients, areas of decreased PBV overestimated final extension of ischemia probably due to inappropriate timing of data acquisition and misery perfusion.ConclusionPBV mapping using FPD CT is a promising tool to predict areas of irrecoverable brain parenchyma in acute thromboembolic stroke. Further validation is necessary before routine use for decision making for interventional thrombectomy.« less

Chiral crossover transition in a finite volume

NASA Astrophysics Data System (ADS)

Shi, Chao; Jia, Wenbao; Sun, An; Zhang, Liping; Zong, Hongshi

2018-02-01

Finite volume effects on the chiral crossover transition of strong interactions at finite temperature are studied by solving the quark gap equation within a cubic volume of finite size L. With the anti-periodic boundary condition, our calculation shows the chiral quark condensate, which characterizes the strength of dynamical chiral symmetry breaking, decreases as L decreases below 2.5 fm. We further study the finite volume effects on the pseudo-transition temperature {T}{{c}} of the crossover, showing a significant decrease in {T}{{c}} as L decreases below 3 fm. Supported by National Natural Science Foundation of China (11475085, 11535005, 11690030, 51405027), the Fundamental Research Funds for the Central Universities (020414380074), China Postdoctoral Science Foundation (2016M591808) and Open Research Foundation of State Key Lab. of Digital Manufacturing Equipment & Technology in Huazhong University of Science & Technology (DMETKF2015015)

Nocturnal polyuria and decreased serum testosterone: is there an association in men with lower urinary tract symptoms?

PubMed

Kim, Jin Wook; Oh, Mi Mi; Yoon, Cheol Yong; Bae, Jae Hyun; Kim, Je Jong; Moon, Du Geon

2014-05-01

To investigate the putative association between nocturia and decreased serum testosterone in men with lower urinary tract symptoms. Frequency volume charts and serum testosterone levels of patients visiting the outpatient clinic for lower urinary tract symptoms were collected and analyzed. Age, prostate volume, body mass index and the presence of comorbidities were accounted for. Frequency volume charts were analyzed for pathophysiological components of nocturnal polyuria, global polyuria, decreased nocturnal bladder capacity and increased frequency to identify associated risks. Frequency volume charts were also used to chart 8-h changes of volume, frequency and capacity to identify time diurnal interactions with risk factors based on serum testosterone levels. A total of 2180 patients were enrolled in the study. Multivariate analysis showed testosterone decreased 0.142 ng/mL for every increase in nocturia, independent of other factors. Logistic regression analysis showed a significant difference between pathophysiological components. Decreased testosterone was shown to carry a significant independent risk for overall nocturia (odds ratio 1.60, 95% confidence interval 1.013-2.527, P = 0.044), and particularly nocturnal polyuria (odds ratio 1.934, 95% confidence interval 1.001-3.737, P = 0.027). Repeated measurement models showed patients with serum testosterone below 2.50 ng/mL to have a paradoxical increase in nocturnal urine volume at night. Nocturia, especially nocturnal polyuria, is associated with decreased serum testosterone. Patients with low serum testosterone show increased nocturnal urine output. © 2013 The Japanese Urological Association.

Effects of 30 day simulated microgravity and recovery on fluid homeostasis and renal function in the rat

NASA Technical Reports Server (NTRS)

Tucker, Bryan J.; Mendonca, Margarida M.

1995-01-01

Transition from a normal gravitational environment to that of microgravity eventually results in decreased plasma and blood volumes, increasing with duration of exposure to microgravity. This loss of vascular fluid is presumably due to negative fluid and electrolyte balance and most likely contributes to the orthostatic intolerance associated with the return to gravity. The decrease in plasma volume is presumed to be a reflection of a concurrent decrease in extracellular fluid volume with maintenance of normal plasma-interstitial fluid balance. In addition, the specific alterations in renal function contributing to these changes in fluid and electrolyte homeostasis are potentially responding to neuro-humoral signals that are not consistent with systemic fluid volume status. We have previously demonstrated an early increase in both glomerular filtration rate and extracellular fluid volume and that this decreases towards control values by 7 days of simulated microgravity. However, longer duration studies relating these changes to plasma volume alterations and the response to return to orthostasis have not been fully addressed. Male Wistar rats were chronically cannulated, submitted to 30 days heat-down tilt (HDT) and followed for 7 days after return to orthostasis from HDT. Measurements of renal function and extracellular and blood volumes were performed in the awake rat.

Mechanisms of decreased left ventricular preload during continuous positive pressure ventilation in ARDS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dhainaut, J.F.; Devaux, J.Y.; Monsallier, J.F.

1986-07-01

Continuous positive pressure ventilation is associated with a reduction in left ventricular preload and cardiac output, but the mechanisms responsible are controversial. The decrease in left ventricular preload may result exclusively from a decreased systemic venous return due to increased pleural pressure, or from an additional effect such as decreased left ventricular compliance. To determine the mechanisms responsible, we studied the changes in cardiac output induced by continuous positive pressure ventilation in eight patients with the adult respiratory distress syndrome. We measured cardiac output by thermodilution, and biventricular ejection fraction by equilibrium gated blood pool scintigraphy. Biventricular end-diastolic volumes weremore » then calculated by dividing stroke volume by ejection fraction. As positive end-expiratory pressure increased from 0 to 20 cm H/sub 2/O, stroke volume and biventricular end-diastolic volumes fell about 25 percent, and biventricular ejection fraction remained unchanged. At 20 cm H/sub 2/O positive end-expiratory pressure, volume expansion for normalizing cardiac output restored biventricular end-diastolic volumes without markedly changing biventricular end-diastolic transmural pressures. The primary cause of the reduction in left ventricular preload with continuous positive pressure ventilation appears to be a fall in venous return and hence in right ventricular stroke volume, without evidence of change in left ventricular diastolic compliance.« less

Biodegradation of BOD and ammonia-free using bacterial consortium in aerated fixed film bioreactor (AF2B)

NASA Astrophysics Data System (ADS)

Prayitno, Rulianah, Sri; Saroso, Hadi; Meilany, Diah

2017-06-01

BOD and Ammonia-free (NH3-N) are pollutants of hospital wastewater which often exceed the quality standards. It is because biological processes in wastewater treatment plant (WWTP) have not been effective in degrading BOD and NH3-N. Therefore, a study on factors that influence the biodegradation of BOD and NH3-N by choosing the type of bacteria to improve the mechanisms of biodegradation processes is required. Bacterial consortium is a collection of several types of bacteria obtained from isolation process, which is known to be more effective than a single bacterial in degrading pollutants. On the other hand, AF2B is a type of reactor in wastewater treatment system. The AF2B contains a filter media that has a large surface area so that the biodegradation process of pollutants by microorganism can be improved. The objective of this research is to determine the effect of volume of starter and air supplies on decreasing BOD and NH3-N in hospital wastewater using bacterial consortium in the AF2B on batch process. The research was conducted in three stages: the making of the growth curve of the bacterial consortium, bacterial consortium acclimatization, and hospital wastewater treatment in the AF2B with batch process. The variables used are the volume of starter (65%, 75%, and 85% in volume) and air supplies (2.5, 5, and 7.5 L/min). Meanwhile, the materials used are hospital wastewater, bacterial consortium (Pseudomonas diminuta, Pseudomonas capica, Bacillius sp, and Nitrobacter sp), blower, and AF2B. AF2B is a plastic basin containing a filter media with a wasp-nest shape used as a medium for growing the bacterial consortium. In the process of making the growth curve, a solid form of bacterial consortium was dissolved in sterilized water, then grown in a nutrient broth (NB). Then, shaking and sampling were done at any time to determine the path growth of bacterial consortium. In the acclimatization process, bacterial isolates were grown using hospital wastewater as a media that was added gradually, followed by the addition of nutrients and aeration. Furthermore, in the biodegradation process of AF2B, the result of acclimatization (as a starter) was fed into the AF2B, then added to the hospital wastewater at a certain volume (as variables), and followed by aeration at a certain flow rate (as variables). Sampling was done at any time to determine the decrease of the concentration of BOD, NH3-N, and MLSS (Mixed Liqour Suspended Solid). BOD and Ammonia-free analyses were conducted using winkler bottle titration and spectrophotometry method. MLSS analysis used gravimetric methods. The results of the research shos that the volume of starter 85% (v) and air supplies of 7.5 L/min can reduce BOD and NH3-N of 92% and 76% respectively. Besides that, AF2B and bacterial consortium have a great ability and are very fast in degrading BOD and NH3-N.

Effects of reduced return activated sludge flows and volume on anaerobic zone performance for a septic wastewater biological phosphorus removal system.

PubMed

Magro, Daniel; Elias, Steven L; Randall, Andrew Amis

2005-01-01

Enhanced biological phosphorous removal (EBPR) performance was found to be adequate with reduced return-activated sludge (RAS) flows (50% of available RAS) to the anaerobic tank and smaller-than-typical anaerobic zone volume (1.08 hours hydraulic retention time [HRT]). Three identical parallel biological nutrient removal pilot plants were fed with strong, highly fermented (160 mg/L volatile fatty acids [VFAs]), domestic and industrial wastewater from a full-scale wastewater treatment facility. The pilot plants were operated at 100, 50, 40, and 25% RAS (percent of available RAS) flows to the anaerobic tank, with the remaining RAS to the anoxic tank. In addition, varying anaerobic HRT (1.08 and 1.5 hours) and increased hydraulic loading (35% increase) were examined. The study was divided into four phases, and the effect of these process variations on EBPR were studied by having one different variable between two identical systems. The most significant conclusion was that returning part of the RAS to the anaerobic zone did not decrease EBPR performance; instead, it changed the location of phosphorous release and uptake. Bringing less RAS to the anaerobic and more to the anoxic tank decreased anaerobic phosphorus release and increased anoxic phosphorus release (or decreased anoxic phosphorus uptake). Equally important is that, with VFA-rich influent wastewater, excessive anaerobic volume was shown to hurt overall phosphorus removal, even when it resulted in increased anaerobic phosphorus release.

Adaptive changes in pancreas post Roux-en-Y gastric bypass induced weight loss.

PubMed

Lautenbach, A; Wernecke, M; Riedel, N; Veigel, J; Yamamura, J; Keller, S; Jung, R; Busch, P; Mann, O; Knop, F K; Holst, J J; Meier, J J; Aberle, J

2018-05-16

Obesity has been shown to trigger adaptive increases in pancreas parenchymal and fat volume. Consecutively, pancreatic steatosis may lead to beta-cell dysfunction. However, it is not known, whether the pancreatic tissue components decrease with weight loss and pancreatic steatosis is reversible following RYGB. Therefore, the objective of the study was to investigate the effects of RYGB-induced weight loss on pancreatic volume and glucose homeostasis. 11 patients were recruited in the Obesity Centre of the University Medical Centre Hamburg-Eppendorf. Before and 6 months after RYGB, total GLP-1 levels were measured during OGTT. To assess changes in visceral adipose tissue and pancreatic volume, MRI was performed. Measures of glucose homeostasis and insulin indices were assessed. Fractional beta-cell area was estimated by correlation with the C-peptide-to-glucose ratio, beta-cell mass was calculated by the product of beta-cell area and pancreas parenchymal weight. Pancreas volume decreased from 83.8 (75.7-92.0) to 70.5 (58.8-82.3) cm 3 [mean (95% CI), p=0.001]. The decrease in total volume was associated with a significant decrease in fat volume. Fasting insulin and C-peptide were lower post RYGB. HOMA-IR levels decreased, whereas insulin sensitivity increased (p=0.03). This was consistent with a reduction in the estimated beta-cell area and mass. Following RYGB, pancreatic volume and steatosis adaptively decreased to "normal" levels with accompanying improvement in glucose homeostasis. Moreover, obesity-driven beta-cell expansion seems to be reversible, however future studies must define a method to more accurately estimate functional beta-cell mass to increase our understanding of glucose homeostasis after RYGB. This article is protected by copyright. All rights reserved.

Brain volumetric changes and cognitive ageing during the eighth decade of life

PubMed Central

Dickie, David Alexander; Cox, Simon R.; Valdes Hernandez, Maria del C.; Corley, Janie; Royle, Natalie A.; Pattie, Alison; Aribisala, Benjamin S.; Redmond, Paul; Muñoz Maniega, Susana; Taylor, Adele M.; Sibbett, Ruth; Gow, Alan J.; Starr, John M.; Bastin, Mark E.; Wardlaw, Joanna M.; Deary, Ian J.

2015-01-01

Abstract Later‐life changes in brain tissue volumes—decreases in the volume of healthy grey and white matter and increases in the volume of white matter hyperintensities (WMH)—are strong candidates to explain some of the variation in ageing‐related cognitive decline. We assessed fluid intelligence, memory, processing speed, and brain volumes (from structural MRI) at mean age 73 years, and at mean age 76 in a narrow‐age sample of older individuals (n = 657 with brain volumetric data at the initial wave, n = 465 at follow‐up). We used latent variable modeling to extract error‐free cognitive levels and slopes. Initial levels of cognitive ability were predictive of subsequent brain tissue volume changes. Initial brain volumes were not predictive of subsequent cognitive changes. Brain volume changes, especially increases in WMH, were associated with declines in each of the cognitive abilities. All statistically significant results were modest in size (absolute r‐values ranged from 0.114 to 0.334). These results build a comprehensive picture of macrostructural brain volume changes and declines in important cognitive faculties during the eighth decade of life. Hum Brain Mapp 36:4910–4925, 2015. © 2015 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc PMID:26769551

Decrease in cortisol reverses human hippocampal atrophy following treatment of Cushing's disease.

PubMed

Starkman, M N; Giordani, B; Gebarski, S S; Berent, S; Schork, M A; Schteingart, D E

1999-12-15

Decreased hippocampal volume is observed in patients with Cushing's syndrome and other conditions associated with elevated cortisol levels, stress, or both. Reversibility of hippocampal neuronal atrophy resulting from stress occurs in animals. Our study investigated the potential for reversibility of human hippocampal atrophy. The study included 22 patients with Cushing's disease. Magnetic resonance brain imaging was performed prior to transsphenoidal microadenomectomy and again after treatment. Following treatment, hippocampal formation volume (HFV) increased by up to 10%. The mean percent change (3.2 +/- 2.5) was significantly greater (p < .04) than that of the comparison structure, caudate head volume (1.5 +/- 3.4). Increase in HFV was significantly associated with magnitude of decrease in urinary free cortisol (r = -.61, p < .01). This relationship strengthened after adjustments for age, duration of disease, and months elapsed since surgery (r = -.70, p < .001). There was no significant correlation between caudate head volume change and magnitude of cortisol decrease. Changes in human HFV associated with sustained hypercortisolemia are reversible, at least in part, once cortisol levels decrease. While many brain regions are likely affected by hypercortisolemia, the human hippocampus exhibits increased sensitivity to cortisol, affecting both volume loss and recovery.

[Runoff and sediment yielding processes on red soil engineering accumulation containing gravels by a simulated rainfall experiment].

PubMed

Shi, Qian-hua; Wang, Wen-long; Guo, Ming-ming; Bai, Yun; Deng, Li-qiang; Li, Jian-ming; Li, Yao-lin

2015-09-01

Engineering accumulation formed in production and construction projects is characterized by unique structure and complex material composition. Characteristics of soil erosion on the engineering accumulation significantly differ from those on farmland. An artificially simulated rainfall experiment was carried out to investigate the effects of rainfall intensity on the processes of runoff and sediment yielding on the engineering accumulation of different gravel contents (0%, 10%, 20% and 30%) in red soil regions. Results showed that the initial time of runoff generation decreased with increases in rainfall intensity and gravel content, the decreased amplitudes being about 48.5%-77.9% and 4.2%-34.2%, respectively. The initial time was found to be a power function of rainfall intensity. Both runoff velocity and runoff rate manifested a trend of first rising and then in a steady state with runoff duration. Rainfall intensity was found to be the main factor influencing runoff velocity and runoff rate, whereas the influence of gravel content was not significant. About 10% of gravel content was determined to be a critical value in the influence of gravel content on runoff volume. For the underlying surface of 10% gravel content, the runoff volume was least at rainfall intensity of 1.0 mm · min(-1) and maximum at rainfall intensity of greater than 1.0 mm · min(-1). The runoff volume in- creased 10%-60% with increase in rainfall intensity. Sediment concentration showed a sharp decline in first 6 min and then in a stable state in rest of time. Influence of rainfall intensity on sediment concentration decreased as gravel content increased. Gravels could reduce sediment yield significantly at rainfall intensity of greater than 1.0 mm · min(-1). Sediment yield was found to be a linear function of rainfall intensity and gravel content.

Timber Volume in Eastern South Dakota, 1980

Treesearch

Ronald L. Hackett

1982-01-01

Eastern South Dakota's 113,600 acres of commercial forest land supported 51.9 million cubic feet of growing stock in 1981. This is a decrease in timber volume of 24 percent since the last inventory in 1965. the decrease was entirely in hardwood species. Cottonwood is the most abundant tree species -- it accounts for 33 percent of the growing-stock volume and...

Regional Blood Volume and Peripheral Blood Flow in the Postural Tachycardia Syndrome

PubMed Central

Stewart, Julian M.; Montgomery, Leslie D.

2015-01-01

Variants of postural tachycardia syndrome (POTS) are associated with increased (“high flow” POTS, HFP), decreased (“low flow POTS”, LFP) and normal (“normal flow POTS”, NFP) blood flow measured in the lower extremities while supine. We propose that postural tachycardia is related to thoracic hypovolemia during orthostasis but that the patterns of peripheral blood flow relate to different mechanisms for thoracic hypovolemia. We studied 37 POTS patients aged 14-21 years: 14 LFP, 15 NFP and 8 HFP patients and 12 healthy control subjects. Peripheral blood flow was measured supine by venous occlusion strain gauge plethysmography of the forearm and calf in order to subgroup patients. Using indocyanine green techniques we showed decreased cardiac index (CI) and increased total peripheral resistance (TPR) in LFP, increased CI and decreased TPR in HFP, and unchanged CI and TPR in NFP while supine compared to control subjects. Blood volume tended to be decreased in LFP compared to control subjects. We used impedance plethysmography to assess regional blood volume redistribution during upright tilt. Thoracic blood volume decreased while splanchnic, pelvic and leg blood volumes increased for all subjects during orthostasis, but were markedly lower than control for all POTS groups. Splanchnic volume was increased in NFP and LFP. Pelvic blood volume was increased in HFP only. Calf volume was increased above control in HFP and LFP. The results support the hypothesis of [at least] three pathophysiologic variants of POTS distinguished by peripheral blood flow related to characteristic changes in regional circulations. The data demonstrate enhanced thoracic hypovolemia during upright tilt and confirm that POTS is related to inadequate cardiac venous return during orthostasis. PMID:15117717

Physiological neuronal decline in healthy aging human brain - An in vivo study with MRI and short echo-time whole-brain (1)H MR spectroscopic imaging.

PubMed

Ding, Xiao-Qi; Maudsley, Andrew A; Sabati, Mohammad; Sheriff, Sulaiman; Schmitz, Birte; Schütze, Martin; Bronzlik, Paul; Kahl, Kai G; Lanfermann, Heinrich

2016-08-15

Knowledge of physiological aging in healthy human brain is increasingly important for neuroscientific research and clinical diagnosis. To investigate neuronal decline in normal aging brain eighty-one healthy subjects aged between 20 and 70years were studied with MRI and whole-brain (1)H MR spectroscopic imaging. Concentrations of brain metabolites N-acetyl-aspartate (NAA), choline (Cho), total creatine (tCr), myo-inositol (mI), and glutamine+glutamate (Glx) in ratios to internal water, and the fractional volumes of brain tissue were estimated simultaneously in eight cerebral lobes and in cerebellum. Results demonstrated that an age-related decrease in gray matter volume was the largest contribution to changes in brain volume. Both lobar NAA and the fractional volume of gray matter (FVGM) decreased with age in all cerebral lobes, indicating that the decreased NAA was predominantly associated with decreased gray matter volume and neuronal density or metabolic activity. In cerebral white matter Cho, tCr, and mI increased with age in association with increased fractional volume, showing altered cellular membrane turn-over, energy metabolism, and glial activity in human aging white matter. In cerebellum tCr increased while brain tissue volume decreased with age, showing difference to cerebral aging. The observed age-related metabolic and microstructural variations suggest that physiological neuronal decline in aging human brain is associated with a reduction of gray matter volume and neuronal density, in combination with cellular aging in white matter indicated by microstructural alterations and altered energy metabolism in the cerebellum. Copyright © 2016 Elsevier Inc. All rights reserved.

Shrinking lung syndrome as a manifestation of pleuritis: a new model based on pulmonary physiological studies.

PubMed

Henderson, Lauren A; Loring, Stephen H; Gill, Ritu R; Liao, Katherine P; Ishizawar, Rumey; Kim, Susan; Perlmutter-Goldenson, Robin; Rothman, Deborah; Son, Mary Beth F; Stoll, Matthew L; Zemel, Lawrence S; Sandborg, Christy; Dellaripa, Paul F; Nigrovic, Peter A

2013-03-01

The pathophysiology of shrinking lung syndrome (SLS) is poorly understood. We sought to define the structural basis for this condition through the study of pulmonary mechanics in affected patients. Since 2007, most patients evaluated for SLS at our institutions have undergone standardized respiratory testing including esophageal manometry. We analyzed these studies to define the physiological abnormalities driving respiratory restriction. Chest computed tomography data were post-processed to quantify lung volume and parenchymal density. Six cases met criteria for SLS. All presented with dyspnea as well as pleurisy and/or transient pleural effusions. Chest imaging results were free of parenchymal disease and corrected diffusing capacities were normal. Total lung capacities were 39%-50% of predicted. Maximal inspiratory pressures were impaired at high lung volumes, but not low lung volumes, in 5 patients. Lung compliance was strikingly reduced in all patients, accompanied by increased parenchymal density. Patients with SLS exhibited symptomatic and/or radiographic pleuritis associated with 2 characteristic physiological abnormalities: (1) impaired respiratory force at high but not low lung volumes; and (2) markedly decreased pulmonary compliance in the absence of identifiable interstitial lung disease. These findings suggest a model in which pleural inflammation chronically impairs deep inspiration, for example through neural reflexes, leading to parenchymal reorganization that impairs lung compliance, a known complication of persistently low lung volumes. Together these processes could account for the association of SLS with pleuritis as well as the gradual symptomatic and functional progression that is a hallmark of this syndrome.

Stochastic response of human blood platelets to stimulation of shape changes and secretion.

PubMed Central

Deranleau, D A; Lüthy, R; Lüscher, E F

1986-01-01

Stopped-flow turbidimetric data indicate that platelets stimulated with low levels of thrombin undergo a shape transformation from disc to "sphere" to smaller spiny sphere that is indistinguishable from the shape change induced by ADP through different membrane receptor sites and a dissimilar receptor trigger mechanism. Under conditions where neither secretion nor aggregation occur, the extinction coefficients for total scattering by each of the three platelet forms are independent of the stimulus applied, and both reaction mechanisms can be described as stochastic (Poisson) processes in which the rate constant for the formation of the transient species is equal to the rate constant for its disappearance. This observation is independent of the shape assignment, and as the concentration of thrombin is increased and various storage organelles secrete increasing amounts of their contents into the external medium, the stochastic pattern persists. Progressively larger decreases in the extinction coefficients of the intermediate and final platelet forms, over and above those that reflect shape alterations alone, accompany or parallel the reaction induced by the higher thrombin concentrations. The excess turbidity decrease observed when full secretion occurs can be wholly accounted for by a decrease in platelet volume equal in magnitude to the fraction of the total platelet volume occupied by alpha granules. Platelet activation, as reported by the whole body light scattering of either shape changes alone or shape changes plus parallel (but not necessarily also stochastic) alpha granule secretion, thus manifests itself as a random series of transient events conceivably with its origins in the superposition of a set of more elementary stochastic processes that could include microtubule depolymerization, actin polymerization, and possibly diffusion. Although the real nature of the control mechanism remains obscure, certain properties of pooled stochastic processes suggest that a reciprocal connection between microtubule fragmentation and the assembly of actin-containing pseudopodal structures and contractile elements--processes that may exhibit reciprocal requirements for calcium--might provide a hypothetical basis for a rate-limiting step. PMID:3457375

Detection of low-volume blood loss: compensatory reserve versus traditional vital signs.

PubMed

Stewart, Camille L; Mulligan, Jane; Grudic, Greg Z; Convertino, Victor A; Moulton, Steven L

2014-12-01

Humans are able to compensate for low-volume blood loss with minimal change in traditional vital signs. We hypothesized that a novel algorithm, which analyzes photoplethysmogram (PPG) wave forms to continuously estimate compensatory reserve would provide greater sensitivity and specificity to detect low-volume blood loss compared with traditional vital signs. The compensatory reserve index (CRI) is a measure of the reserve remaining to compensate for reduced central blood volume, where a CRI of 1 represents supine normovolemia and 0 represents the circulating blood volume at which hemodynamic decompensation occurs; values between 1 and 0 indicate the proportion of reserve remaining. Subjects underwent voluntary donation of 1 U (approximately 450 mL) of blood. Demographic and continuous noninvasive vital sign wave form data were collected, including PPG, heart rate, systolic blood pressure, cardiac output, and stroke volume. PPG wave forms were later processed by the algorithm to estimate CRI values. Data were collected from 244 healthy subjects (79 males and 165 females), with a mean (SD) age of 40.1 (14.2) years and mean (SD) body mass index of 25.6 (4.7). After blood donation, CRI significantly decreased in 92% (α = 0.05; 95% confidence interval [CI], 88-95%) of the subjects. With the use of a threshold decrease in CRI of 0.05 or greater for the detection of 1 U of blood loss, the receiver operating characteristic area under the curve was 0.90, with a sensitivity of 0.84 and specificity of 0.86. In comparison, systolic blood pressure (52%; 95% CI, 45-59%), heart rate (65%; 95% CI, 58-72%), cardiac output (47%; 95% CI, 40-54%), and stroke volume (74%; 95% CI, 67-80%) changed in fewer subjects, had significantly lower receiver operating characteristic area under the curve values, and significantly lower specificities for detecting the same volume of blood loss. Consistent with our hypothesis, CRI detected low-volume blood loss with significantly greater specificity than other traditional physiologic measures. These findings warrant further evaluation of the CRI algorithm in actual trauma settings. Diagnostic study, level II.

Regenerate Healing Outcomes in Unilateral Mandibular Distraction Osteogenesis Using Quantitative Histomorphometry

PubMed Central

Schwarz, Daniel A.; Arman, Krikor G.; Kakwan, Mehreen S.; Jamali, Ameen M.; Elmeligy, Ayman A.; Buchman, Steven R.

2015-01-01

Background The authors’ goal was to ascertain regenerate bone-healing metrics using quantitative histomorphometry at a single consolidation period. Methods Rats underwent either mandibular distraction osteogenesis (n=7) or partially reduced fractures (n=7); their contralateral mandibles were used as controls (n=11). External fixators were secured and unilateral osteotomies performed, followed by either mandibular distraction osteogenesis (4 days’ latency, then 0.3 mm every 12 hours for 8 days; 5.1 mm) or partially reduced fractures (fixed immediately postoperatively; 2.1 mm); both groups underwent 4 weeks of consolidation. After tissue processing, bone volume/tissue volume ratio, osteoid volume/tissue volume ratio, and osteocyte count per high-power field were analyzed by means of quantitative histomorphometry. Results Contralateral mandibles had statistically greater bone volume/tissue volume ratio and osteocyte count per high-power field compared with both mandibular distraction osteogenesis and partially reduced fractures by almost 50 percent, whereas osteoid volume/tissue volume ratio was statistically greater in both mandibular distraction osteogenesis specimens and partially reduced fractures compared with contralateral mandibles. No statistical difference in bone volume/tissue volume ratio, osteoid volume/tissue volume ratio, or osteocyte count per high-power field was found between mandibular distraction osteogenesis specimens and partially reduced fractures. Conclusions The authors’ findings demonstrate significantly decreased bone quantity and maturity in mandibular distraction osteogenesis specimens and partially reduced fractures compared with contralateral mandibles using the clinically analogous protocols. If these results are extrapolated clinically, treatment strategies may require modification to ensure reliable, predictable, and improved outcomes. PMID:20463629

Influence of temperature on the single-stage ATAD process predicted by a thermal equilibrium model.

PubMed

Cheng, Jiehong; Zhu, Jun; Kong, Feng; Zhang, Chunyong

2015-06-01

Autothermal thermophilic aerobic digestion (ATAD) is a promising biological process that will produce an effluent satisfying the Class A requirements on pathogen control and land application. The thermophilic temperature in an ATAD reactor is one of the critical factors that can affect the satisfactory operation of the ATAD process. This paper established a thermal equilibrium model to predict the effect of variables on the auto-rising temperature in an ATAD system. The reactors with volumes smaller than 10 m(3) could not achieve temperatures higher than 45 °C under ambient temperature of -5 °C. The results showed that for small reactors, the reactor volume played a key role in promoting auto-rising temperature in the winter. Thermophilic temperature achieved in small ATAD reactors did not entirely depend on the heat release from biological activities during degrading organic matters in sludges, but was related to the ambient temperature. The ratios of surface area-to-effective volume less than 2.0 had less impact on the auto-rising temperature of an ATAD reactor. The influence of ambient temperature on the auto-rising reactor temperature decreased with increasing reactor volumes. High oxygen transfer efficiency had a significant influence on the internal temperature rise in an ATAD system, indicating that improving the oxygen transfer efficiency of aeration devices was a key factor to achieve a higher removal rate of volatile solids (VS) during the ATAD process operation. Compared with aeration using cold air, hot air demonstrated a significant effect on maintaining the internal temperature (usually 4-5 °C higher). Copyright © 2015 Elsevier Ltd. All rights reserved.

The effectiveness of the stabilization/solidification process on the leachability and toxicity of the tannery sludge chromium.

PubMed

Montañés, M T; Sánchez-Tovar, R; Roux, M S

2014-10-01

A stabilization/solidification (S/S) process by using cement was applied to tannery sludge in order to find a safer way of landfilling this waste. The effects of three parameters on the process effectiveness were analysed in terms of leachate toxicity and chromium retention (%). The parameters studied were the relative amount of added water (30-50 wt.%), cement (10-60 wt.% in the solid components), and the use of three different types of cement (clinker with additions of limestone, with additions of limestone and fly ashes, and with additions of pozzolans). Statistical analysis performed by variance analysis and categorical multifactorial tests reveals that all the studied parameters significantly influence the effectiveness of the process. Results showed that chromium retention decreases as the relative amount of cement and water increases, probably due to additional chromium provided by cement and increased in the porosity of the mixtures. Leachate toxicity showed the same minimum value for mixtures with 30% or 40% cement, depending on the type of cement, showing that clinker is the main material responsible for the process effectiveness, and additives (pozzolans or fly ashes) do not improve it. The volume increase is lower as less sludge is replaced by cement and the relative amount of water decreases, and for the cement without additions of fly ashes or pozzolans. Therefore, the latter seems to be the most appropriate cement in spite of being more expensive. This is due to the fact that the minimum toxicity value is achieved with a lower amount of cement; and moreover, the volume increase in the mixtures is lower, minimizing the disposal cost to a landfill. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of dietary interventions on liver volume in humans.

PubMed

Bian, Hua; Hakkarainen, Antti; Lundbom, Nina; Yki-Järvinen, Hannele

2014-04-01

To compare effects of similar weight loss induced either by a short-term low-carbohydrate or by a long-term hypocaloric diet, and to determine effects of high carbohydrate overfeeding on liver total, lean, and fat volumes. Liver total, lean, and fat volumes were measured before and after (i) a 6-day low-carbohydrate diet (n = 17), (ii) a 7-month standard hypocaloric diet (n = 26), and (iii) a 3-week high-carbohydrate diet (n = 17), by combining magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy ((1) H-MRS) techniques. At baseline, three groups were comparable with respect to age, body mass index, liver volumes and the liver fat content. Body weight decreased similarly by the short-term and long-term hypocaloric diets. Liver total volume decreased significantly more during the short-term low-carbohydrate (-22 ± 2%) than the long-term (-7 ± 2%) hypocaloric diet (P < 0.001). This was due to a greater decrease in liver lean volume in the short-term (-20 ± 2%) than the long-term (-4 ± 2%) weight loss group (P < 0.001). Decreases in liver fat were comparable. Liver volume increased by 9 ± 3% due to overfeeding (P< 0.02 for before vs. after). These data support the use of a short-term low-carbohydrate diet whenever a reduction in liver volume is desirable. Overeating carbohydrate is harmful because it increases liver volume. Copyright © 2013 The Obesity Society.

The Effect of Colonoscopy Reimbursement Reductions on Gastroenterologist Practice Behavior.

PubMed

McNeill, Matthew B; Chang, Shannon; Sahebjam, Farhad; Goodman, Adam J; Gross, Seth A; Sigal, Samuel H

2016-06-01

The purpose of this study was to assess the effect of decreased colonoscopy reimbursement on gastroenterologist practice behavior, including time to retirement and procedure volume. In 2015, the Centers for Medicare and Medicaid Services proposed reductions in colonoscopy reimbursements. With new initiatives for increased colorectal cancer screening, it is crucial to understand how reimbursement changes could affect these efforts. Randomly selected respondents from the American College of Gastroenterology membership database were surveyed on incremental changes in practice behavior if colonoscopy reimbursement were to decrease by 10, 20, 30, or 40 %. Data were analyzed using both Pearson's Chi-square and analysis of variance. Two thousand and nine gastroenterologists received the survey with a 16.3 % response rate. Procedure volume significantly decreased with degree of reimbursement reductions (p < 0.001). With a 10 % decrease, 72 % of respondents reported no change in the number of colonoscopies performed. With a 20 % decrease, 39 % would decrease their procedure volume, while 21 % of respondents would increase their procedure volume. With a 30 and 40 % decrease, procedure volume decreased by 48 and 50 %, respectively. In terms of retirement, current plans predict a cumulative retirement rate of 29.4 % at 10 years. More than 42 % of respondents plan to retire after 2030. In the 2014-2023 retirement subgroup (N = 74 responses), there was a significant hastening of retirement year at 20 % (p = 0.016), 30 % (p < 0.001), and 40 % (p < 0.001) reimbursement reductions as compared to baseline responses. Decreasing colonoscopy reimbursements may have a significant effect on the effective gastroenterology work force.

Effect of cytoplasmic volume on developmental competence of buffalo (Bubalus bubalis) embryos produced through hand-made cloning.

PubMed

Panda, Sudeepta K; George, Aman; Saha, Ambika P; Sharma, Ruchi; Manik, Radhey S; Chauhan, Manmohan S; Palta, Prabhat; Singla, Suresh K

2011-06-01

This study examined the effects of cytoplasmic volume on the developmental competence of hand-made cloned buffalo embryos. Two different cell types, that is, buffalo fetal fibroblast (BFF) and buffalo embryonic stem (ES) cell-like cells were taken as donor cell and fused with one, two, or three demicytoplasts to generate embryos with decreased, normal (control), and increased cytoplasmic volume. Using BFF as a nuclear donor, the cleavage rate was similar in all the groups (p > 0.05), but the blastocysts rate was significantly lower (p < 0.05) for embryos generated with decreased cytoplasmic volume. Using ES cell-like cells, the cleavage and blastocyst rate with increased cytoplasmic volume was significantly higher (p < 0.05) compared that with reduced cytoplasmic volume. Blastocysts produced from embryos having increased cytoplasmic volume had significantly higher (p < 0.05) cell number than normal (control) embryos in both BFF and ES cell-like cells groups. Pregnancies were established in all the groups except for the embryos reconstructed with decreased cytoplasmic volume. The pregnancy rate was almost double for embryos reconstructed using increased cytoplasmic volume compared to that with the controls. Most of the pregnancies aborted in the first trimester and one live calf was delivered through Caesarean, which died 4 h after birth.

High Volume Manufacturing and Field Stability of MEMS Products

NASA Astrophysics Data System (ADS)

Martin, Jack

Low volume MEMS/NEMS production is practical when an attractive concept is implemented with business, manufacturing, packaging, and test support. Moving beyond this to high volume production adds requirements on design, process control, quality, product stability, market size, market maturity, capital investment, and business systems. In a broad sense, this chapter uses a case study approach: It describes and compares the silicon-based MEMS accelerometers, pressure sensors, image projection systems, and gyroscopes that are in high volume production. Although they serve several markets, these businesses have common characteristics. For example, the manufacturing lines use automated semiconductor equipment and standard material sets to make consistent products in large quantities. Standard, well controlled processes are sometimes modified for a MEMS product. However, novel processes that cannot run with standard equipment and material sets are avoided when possible. This reliance on semiconductor tools, as well as the organizational practices required to manufacture clean, particle-free products partially explains why the MEMS market leaders are integrated circuit manufacturers. There are other factors. MEMS and NEMS are enabling technologies, so it can take several years for high volume applications to develop. Indeed, market size is usually a strong function of price. This becomes a vicious circle, because low price requires low cost - a result that is normally achieved only after a product is in high volume production. During the early years, IC companies reduced cost and financial risk by using existing facilities for low volume MEMS production. As a result, product architectures are partially determined by capabilities developed for previous products. This chapter includes a discussion of MEMS product architecture with particular attention to the impact of electronic integration, packaging, and surfaces. Packaging and testing are critical, because they are significant factors in MEMS product cost. These devices have extremelyhigh surface/volume ratios, so performance and stability may depend on the control of surface characteristics after packaging. Looking into the future, the competitive advantage of IC suppliers will decrease as small companies learn to integrate MEMS/NEMS devices on CMOS foundry wafers. Packaging challenges still remain, because most MEMS/NEMS products must interact with the environment without degrading stability or reliability. Generic packaging solutions are unlikely. However, packaging subcontractors recognize that MEMS/NEMS is a growth opportunity. They will spread the overhead burden of high-capital-cost-facilities by developing flexible processes in order to package several types of moderate volume integrated MEMS/NEMS products on the same equipment.

High Volume Manufacturing and Field Stability of MEMS Products

NASA Astrophysics Data System (ADS)

Martin, Jack

Low volume MEMS/NEMS production is practical when an attractive concept is implemented with business, manufacturing, packaging, and test support. Moving beyond this to high volume production adds requirements on design, process control, quality, product stability, market size, market maturity, capital investment, and business systems. In a broad sense, this chapter uses a case study approach: It describes and compares the silicon-based MEMS accelerometers, pressure sensors, image projection systems, and gyroscopes that are in high volume production. Although they serve several markets, these businesses have common characteristics. For example, the manufacturing lines use automated semiconductor equipment and standard material sets to make consistent products in large quantities. Standard, well controlled processes are sometimes modified for a MEMS product. However, novel processes that cannot run with standard equipment and material sets are avoided when possible. This reliance on semiconductor tools, as well as the organizational practices required to manufacture clean, particle-free products partially explains why the MEMS market leaders are integrated circuit manufacturers. There are other factors. MEMS and NEMS are enabling technologies, so it can take several years for high volume applications to develop. Indeed, market size is usually a strong function of price. This becomes a vicious circle, because low price requires low cost - a result that is normally achieved only after a product is in high volume production. During the early years, IC companies reduced cost and financial risk by using existing facilities for low volume MEMS production. As a result, product architectures are partially determined by capabilities developed for previous products. This chapter includes a discussion of MEMS product architecture with particular attention to the impact of electronic integration, packaging, and surfaces. Packaging and testing are critical, because they are significant factors in MEMS product cost. These devices have extremely high surface/volume ratios, so performance and stability may depend on the control of surface characteristics after packaging. Looking into the future, the competitive advantage of IC suppliers will decrease as small companies learn to integrate MEMS/NEMS devices on CMOS foundry wafers. Packaging challenges still remain, because most MEMS/NEMS products must interact with the environment without degrading stability or reliability. Generic packaging solutions are unlikely. However, packaging subcontractors recognize that MEMS/NEMS is a growth opportunity. They will spread the overhead burden of high-capital-cost-facilities by developing flexible processes in order to package several types of moderate volume integrated MEMS/NEMS products on the same equipment.

Ultrastructural remodelling of slow skeletal muscle fibres in creatine kinase deficient mice: a quantitative study.

PubMed

Novotová, Marta; Tarabová, Bohumila; Tylková, Lucia; Ventura-Clapier, Renée; Zahradník, Ivan

2016-10-01

Creatine kinase content, isoform distribution, and participation in energy transfer are muscle type specific. We analysed ultrastructural changes in slow muscle fibres of soleus due to invalidation of creatine kinase (CK) to reveal a difference in the remodelling strategy in comparison with fast muscle fibres of gastrocnemius published previously. We have employed the stereological method of vertical sections and electron microscopy of soleus muscles of wild type (WT) and CK-/- mice. The mitochondrial volume density was 1.4× higher but that of sarcoplasmic reticulum (SR) was almost 5× lower in slow CK-/- muscles fibres than in WT fibres. The volume density of terminal cisterns and of t-tubules was also lower in CK-/- than in WT fibres. The analysis of organelle environment revealed increased neighbourhood of mitochondria and A-bands that resulted from the decreased volume density of SR, from relocation of mitochondria along myofibrils, and from intrusion of mitochondria to myofibrils. These processes direct ATP supply closer to the contractile machinery. The decreased interaction between mitochondria and SR suggests reduced dependence of calcium uptake on oxidative ATP production. In conclusion, the architecture of skeletal muscle cells is under control of a cellular program that optimizes energy utilization specifically for a given muscle type.

[Laser's biostimulation in healing or crural ulcerations].

PubMed

Król, P; Franek, A; Huńka-Zurawińska, W; Bil, J; Swist, D; Polak, A; Bendkowski, W

2001-11-01

The objective of this paper was to evaluate effect of laser's biostimulation on the process of healing of crural ulcerations. Three comparative groups of patients, A, B and C, were made at random from the patients with venous crural ulcerations. The group A consisted of 17, the group B 15, the group C 17 patients. The patients in all comparative groups were treated pharmacologically and got compress therapy. Ulcerations at patients in group A were additionally irradiated by light of biostimulation's laser (810 nm) in this way that every time ulcerations got dose of energy 4 J/cm2. The patient's in-group B additionally got blind trial (with placebo in the form of quasi-laserotherapy). The evaluated factors were to estimate how laser's biostimulation causes any changes of the size of the ulcers and of the volume of tissue defect. The speed of changes of size and volume of tissue defect per week was calculated. After the treatment there was statistically significant decrease of size of ulcers in all comparative groups while there was no statistically significant difference between the groups observed. After the treatment there was statistically significant decrease of volume of ulcers only in groups A and C but there was no statistically significant difference between the groups observed.

Regeneration of axotomized olfactory neurons in young and adult locusts quantified by fasciclin I immunofluorescence.

PubMed

Wasser, Hannah; Biller, Alexandra; Antonopoulos, Georgios; Meyer, Heiko; Bicker, Gerd; Stern, Michael

2017-04-01

The olfactory pathway of the locust Locusta migratoria is characterized by a multiglomerular innervation of the antennal lobe (AL) by olfactory receptor neurons (ORNs). After crushing the antenna and thereby severing ORN axons, changes in the AL were monitored. First, volume changes were measured at different times post-crush with scanning laser optical tomography in 5th instar nymphs. AL volume decreased significantly to a minimum volume at 4 days post-crush, followed by an increase. Second, anterograde labeling was used to visualize details in the AL and antennal nerve (AN) during de- and regeneration. Within 24 h post-crush (hpc) the ORN fragments distal to the lesion degenerated. After 48 hpc, regenerating fibers grew through the crush site. In the AL, labeled ORN projections disappeared completely and reappeared after a few days. A weak topographic match between ORN origin on the antenna and the position of innervated glomeruli that was present in untreated controls did not reappear after regeneration. Third, the cell surface marker fasciclin I that is expressed in ORNs was used for quantifying purposes. Immunofluorescence was measured in the AL during de- and regeneration in adults and 5th instar nymphs: after a rapid but transient, decrease, it reappeared. Both processes happen faster in 5th instar nymphs than in adults.

Effect of Aspergillus niger xylanase on dough characteristics and bread quality attributes.

PubMed

Ahmad, Zulfiqar; Butt, Masood Sadiq; Ahmed, Anwaar; Riaz, Muhammad; Sabir, Syed Mubashar; Farooq, Umar; Rehman, Fazal Ur

2014-10-01

The present study was conducted to investigate the impact of various treatments of xylanase produced by Aspergillus niger applied in bread making processes like during tempering of wheat kernels and dough mixing on the dough quality characteristics i.e. dryness, stiffness, elasticity, extensibility, coherency and bread quality parameters i.e. volume, specific volume, density, moisture retention and sensory attributes. Different doses (200, 400, 600, 800 and 1,000 IU) of purified enzyme were applied to 1 kg of wheat grains during tempering and 1 kg of flour (straight grade flour) during mixing of dough in parallel. The samples of wheat kernels were agitated at different intervals for uniformity in tempering. After milling and dough making of both types of flour (having enzyme treatment during tempering and flour mixing) showed improved dough characteristics but the improvement was more prominent in the samples receiving enzyme treatment during tempering. Moreover, xylanase decreased dryness and stiffness of the dough whereas, resulted in increased elasticity, extensibility and coherency and increase in volume & decrease in bread density. Xylanase treatments also resulted in higher moisture retention and improvement of sensory attributes of bread. From the results, it is concluded that dough characteristics and bread quality improved significantly in response to enzyme treatments during tempering as compared to application during mixing.

Volumetric analysis of chronic maxillary atelectasis.

PubMed

Lin, Giant C; Sedaghat, Ahmad R; Bleier, Benjamin S; Holbrook, Eric H; Busaba, Nicolas Y; Yoon, Michael K; Gray, Stacey T

2015-01-01

The relationship between orbit and maxillary sinus volumes in patients with chronic maxillary atelectasis (CMA), commonly known as silent sinus syndrome if enophthalmos is present, is poorly understood. A retrospective review of 22 patients who underwent endoscopic sinus surgery (ESS) for CMA from 2005 to 2013 was performed. Computed tomography (CT) images were analyzed using OsiriX 5.8.2 software for volumetric analysis of the orbit and maxillary sinus at presentation and after surgical treatment with ESS. Pretreatment mean orbit volumes on the diseased side (DS) and the contralateral side (CS) were 29.22 and 26.50 mL, respectively (p < 0.001); mean sinus volumes on the DS and CS were 8.51 and 17.20 mL, respectively (p < 0.001); and pretreatment mean midorbit heights (MOHs) on the DS and CS were 3.39 cm and 3.07 cm, respectively (p < 0.001). The percent decrease in sinus volume on the DS compared to that on the CS did not correlate significantly with the percent orbit-volume increase. Enophthalmos was present in nine (41%) patients, and diplopia was present in three (14%) patients. The measured degree of increased orbit volume and decreased sinus volume secondary to CMA did not significantly predict the presence of enophthalmos at presentation. Seven patients underwent sinus CT more than 6 months after ESS. In these patients, orbit volume on the DS decreased from 29.67 to 27.52 mL (p = 0.005), and sinus volume on the DS increased from 9.78 to 11.84 mL (p = 0.08). Volumetric analysis is a powerful and novel method for objectively demonstrating the degree of orbit expansion and maxillary sinus contraction seen with CMA. Spontaneous maxillary sinus expansion and a decrease in orbit volume can occur after ESS, but post-ESS volumes do not return to the normal volume of the CS.

Tidal inlet response to sediment infilling of the associated bay and possible implications of human activities: the Marennes-Oléron Bay and the Maumusson Inlet, France

NASA Astrophysics Data System (ADS)

Bertin, Xavier; Chaumillon, Eric; Sottolichio, Aldo; Pedreros, Rodrigo

2005-06-01

Tidal inlet characteristics are controlled by wave energy, tidal range, tidal prism, sediment supply and direction and rates of sand delivered to the inlet. This paper deals with the relations between inlet and lagoon evolutions, linked by the tidal prism. Our study is focused on the Maumusson Inlet and the Marennes-Oléron Bay (first oyster farming area in Europe), located on the western coast of France. The tidal range (2-6 m) and wave climate (mean height: 1.5 m) place this tidal inlet system in the mixed energy (tide, waves), tide-dominated category. The availability of high-resolution bathymetric data since 1824 permits to characterise and quantify accurately morphological changes of both the inlet and the tidal bay. Since 1824, sediment filling of the tidal bay has led to a 20% decrease in its water volume, and a 35% reduction of the inlet throat section. Furthermore, the bay is subjected to a very high anthropic pressure, mainly related to oyster farming. Thus, both natural and human-related processes seem relevant to explain high sedimentation rates. Current measurements, hydrodynamic modelling and cross-sectional area of the inlet throat are used in order to quantify tidal prism changes since 1824. Both flood and ebb tidal prism decreased by 35%. Decrease in the Marennes-Oléron Bay water volume is inferred to be responsible for a part of tidal prism decrease at the inlet. Tidal prisms decrease may also be explained by an increase in frictional resistance to tidal wave propagation, due to a general shoaling and oyster farms in the bay. A conceptual model is proposed, taking into account natural and human-related sedimentation processes, and explaining tidal inlet response to tidal bay evolutions.

Cerebral edema, mass effects, and regional blood volume in man.

PubMed

Penn, R D; Kurtz, D

1977-03-01

The authors conducted quantitative analysis of computerized tomography (CT) scans to measure tumor size, cerebral edema, and regional blood volume in man. Mass lesions without edema caused a local reduction in blood volume. Cerebral edema also reduced blood volume in proportion to its severity. Consideration of the electrolyte changes and water shifts in white-matter edema suggested that the decrease in absorption coefficient seen in CT scans was due to the increase in water content. Thus, in cerebral edema separation of blood vessels as well as increased interstitial pressure decrease blood volume, and the regional differences in turn reflect pressure gradients within the brain.

Decreasing effect and mechanism of moisture content of sludge biomass by granulation process.

PubMed

Zhao, Xia; Xu, Hao; Shen, Jimin; Yu, Bo; Wang, Xiaochun

2016-01-01

Disposal of a high volume of sludge significantly raises water treatment costs. A method for cultivating aerobic granules in a sequencing batch airlift bioreactor to significantly produce lower moisture content is described. Results indicate that optimization of settling time and control of the shear stresses acted on the granules. The diameter of the granule was within the range of 1.0-4.0 mm, and its sludge volume index was stabilized at 40-50 mL g(-1). Its specific gravity was increased by a factor of 0.0392, and specific oxygen uptake rate reached 60.126 mg h(-1) g(-1). Moreover, the percentage of its moisture content in the reactor ranged from 96.73% to 97.67%, and sludge volume was reduced to approximately 60%, greatly due to the presence of extracellular polymeric substances in the granules, as well as changes in their hydrophobic protein content. The removal rate of chemical oxygen demand and [Formula: see text] reaches up to 92.6% and 98%, respectively. The removal rates of total phosphorus is over 85%. Therefore, aerobic granular sludge process illustrates a good biological activity.

Compositional effects on the chemorheological properties and forming behavior of aqueous alumina-poly(vinyl alcohol) gelcasting suspensions

NASA Astrophysics Data System (ADS)

Morissette, Sherry L.

A new gelcasting system based on aqueous, alumina-poly(vinyl alcohol) (PVA) suspensions cross-linked by an organotitanate coupling agent has been developed. Both the chemorheological properties and forming behavior of this system exhibited a strong compositional dependence. A sol- gel phase diagram was established, which yielded the critical titanium concentration [Ti] c required for gelation at a given PVA volume fraction, as well as the minimum PVA volume fraction ( fminPVA = 0.0245) and titanium PVA concentration ([Ti]min = 9.984 x 10--4 g Ti/ml) below which gelation was not observed irrespective of solution composition. The gelation time of suspensions of constant PVA volume fraction ( fsolnPVA ) decreased with increasing cross-linking agent concentration, PVA temperature, and solids volume fraction. The steady-state viscosity and elastic modulus of polymer solutions ( fsolnPVA = 0.05) of varying [Ti] were well described by the PVA percolation model, giving scaling exponents of 0.84 and 1.79, respectively. The steady-state elastic modulus of gel casting suspensions, which provides a measure of their handling strength in the as-gelled state, increased with increasing solids volume fraction. Gelcasting suspensions were used as feedstock for solid free-form fabrication (SFF) of ceramic components. The influence of processing conditions (e.g., tip diameter, mixing rate, table speed, etc.) and suspension rheology on deposition behavior was investigated. Continuous printablity was achieved for tip diameters ranging from dt = 0.254 -- 1.370 mm for all mixing rates (Rmix 5 -- 300 rpm) and suspension compositions (i.e., fAl2O3 = 0.45, φPVA = 0.275, [Ti] 0 -- 6.30 x 10--3 g Ti/ml) probed, where the minimum tip diameter for continuous printing was 0.203 mm. Printed lines were uniform with good edge definition. Line dimensions were independent of mixing rate for the given process conditions. The as-cast alumina volume fraction ( fAl2O3 ) depended on casting conditions and cross-linking agent concentration, where fAl2O3 decreased with increasing tip diameter and increased with increasing cross-linking agent concentration. Free-fomied Al2O3 components exhibited uniform particle packing and had minimal macro-defects (e.g., slumping or stair casing) and no detectable micro-defects (e.g., bubbles or cracking).

A new approach to investigate an eruptive paroxysmal sequence using camera and strainmeter networks: Lessons from the 3-5 December 2015 activity at Etna volcano

NASA Astrophysics Data System (ADS)

Bonaccorso, A.; Calvari, S.

2017-10-01

Explosive sequences are quite common at basaltic and andesitic volcanoes worldwide. Studies aimed at short-term forecasting are usually based on seismic and ground deformation measurements, which can be used to constrain the source region and quantify the magma volume involved in the eruptive process. However, during single episodes of explosive sequences, integration of camera remote sensing and geophysical data are scant in literature, and the total volume of pyroclastic products is not determined. In this study, we calculate eruption parameters for four powerful lava fountains occurring at the main and oldest Mt. Etna summit crater, Voragine, between 3 and 5 December 2015. These episodes produced impressive eruptive columns and plume clouds, causing lapilli and ash fallout to more than 100 km away. We analyse these paroxysmal events by integrating the images recorded by a network of monitoring cameras and the signals from three high-precision borehole strainmeters. From the camera images we calculated the total erupted volume of fluids (gas plus pyroclastics), inferring amounts from 1.9 ×109 m3 (first event) to 0.86 ×109 m3 (third event). Strain changes recorded during the first and most powerful event were used to constrain the depth of the source. The ratios of strain changes recorded at two stations during the four lava fountains were used to constrain the pyroclastic fraction for each eruptive event. The results revealed that the explosive sequence was characterized by a decreasing trend of erupted pyroclastics with time, going from 41% (first event) to 13% (fourth event) of the total erupted pyroclastic volume. Moreover, the volume ratio fluid/pyroclastic decreased markedly in the fourth and last event. To the best of our knowledge, this is the first time ever that erupted volumes of both fluid and pyroclastics have been estimated for an explosive sequence from a monitoring system using permanent cameras and high precision strainmeters. During future explosive paroxysmal sequences this new approach might help in monitoring their evolution also to understand when/if they are going to finish. Knowledge of the total gas and pyroclastic fractions erupted during each lava fountain episode would improve our understanding of their processes and eruptive behaviour.

Entrance-length dendritic plate heat exchangers

DOE PAGES

Bejan, A.; Alalaimi, M.; Sabau, A. S.; ...

2017-07-17

We explore the idea that the highest heat transfer rate between two fluids in a given volume is achieved when plate channel lengths are given by the thermal entrance length, i.e., when the thermal boundary layers meet at the exit of each channel. The overall design can be thought of an elemental construct of a dendritic heat exchanger, which consists of two tree-shaped streams arranged in cross flow. Every channel is as long as the thermal entrance length of the developing flow that resides in that channel. The results indicate that the overall design will change with the total volumemore » and total number of channels. We found that the lengths of the surfaces swept in cross flow would have to decrease sizably as number of channels increases, while exhibiting mild decreases as total volume increases. The aspect ratio of each surface swept by fluid in cross flow should be approximately square, independent of total number of channels and volume. We also found that the minimum pumping power decreases sensibly as the total number of channels and the volume increase. FurtherThe maximized heat transfer rate per unit volume increases sharply as the total volume decreases, in agreement with the natural evolution toward miniaturization in technology.« less

Entrance-length dendritic plate heat exchangers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bejan, A.; Alalaimi, M.; Sabau, A. S.

We explore the idea that the highest heat transfer rate between two fluids in a given volume is achieved when plate channel lengths are given by the thermal entrance length, i.e., when the thermal boundary layers meet at the exit of each channel. The overall design can be thought of an elemental construct of a dendritic heat exchanger, which consists of two tree-shaped streams arranged in cross flow. Every channel is as long as the thermal entrance length of the developing flow that resides in that channel. The results indicate that the overall design will change with the total volumemore » and total number of channels. We found that the lengths of the surfaces swept in cross flow would have to decrease sizably as number of channels increases, while exhibiting mild decreases as total volume increases. The aspect ratio of each surface swept by fluid in cross flow should be approximately square, independent of total number of channels and volume. We also found that the minimum pumping power decreases sensibly as the total number of channels and the volume increase. FurtherThe maximized heat transfer rate per unit volume increases sharply as the total volume decreases, in agreement with the natural evolution toward miniaturization in technology.« less

Strengthening and Improving Yield Asymmetry of Magnesium Alloys by Second Phase Particle Refinement Under the Guidance of Integrated Computational Materials Engineering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Dongsheng; Lavender, Curt

2015-05-08

Improving yield strength and asymmetry is critical to expand applications of magnesium alloys in industry for higher fuel efficiency and lower CO 2 production. Grain refinement is an efficient method for strengthening low symmetry magnesium alloys, achievable by precipitate refinement. This study provides guidance on how precipitate engineering will improve mechanical properties through grain refinement. Precipitate refinement for improving yield strengths and asymmetry is simulated quantitatively by coupling a stochastic second phase grain refinement model and a modified polycrystalline crystal viscoplasticity φ-model. Using the stochastic second phase grain refinement model, grain size is quantitatively determined from the precipitate size andmore » volume fraction. Yield strengths, yield asymmetry, and deformation behavior are calculated from the modified φ-model. If the precipitate shape and size remain constant, grain size decreases with increasing precipitate volume fraction. If the precipitate volume fraction is kept constant, grain size decreases with decreasing precipitate size during precipitate refinement. Yield strengths increase and asymmetry approves to one with decreasing grain size, contributed by increasing precipitate volume fraction or decreasing precipitate size.« less

Exercise science: research to sustain and enhance performance

NASA Astrophysics Data System (ADS)

Wingo, Jonathan E.

2013-05-01

Cardiovascular adjustments accompanying exercise in high ambient temperatures are likely responsible for diminished aerobic capacity and performance in such conditions. These adjustments include a phenomenon known as cardiovascular drift in which heart rate rises and stroke volume declines progressively over time during constant-rate exercise. A variety of factors modulate the magnitude of cardiovascular drift, e.g., elevated core and skin temperatures, dehydration, and exercise intensity. Regardless of the mode of manipulation, decreases in stroke volume associated with cardiovascular drift result in directionally and proportionally similar decreases in maximal aerobic capacity. Maximal aerobic capacity is determined by maximal heart rate, maximal tissue oxygen extraction, and maximal stroke volume. Because maximal heart rate and maximal tissue oxygen extraction are unaffected during exercise in the heat, decreased stroke volume associated with cardiovascular drift likely persists during maximal efforts and explains the decrease in maximal aerobic capacity. Decreased maximal aerobic capacity results in a greater perceptual and physiological strain accompanying any given level of work. Therefore, sustaining and enhancing performance involves sophisticated monitoring of physiological strain combined with development of countermeasures that mitigate the magnitude of deleterious phenomena like cardiovascular drift.

EEG based zero-phase phase-locking value (PLV) and effects of spatial filtering during actual movement.

PubMed

Jian, Wenjuan; Chen, Minyou; McFarland, Dennis J

2017-04-01

Phase-locking value (PLV) is a well-known feature in sensorimotor rhythm (SMR) based BCI. Zero-phase PLV has not been explored because it is generally regarded as the result of volume conduction. Because spatial filters are often used to enhance the amplitude (square root of band power (BP)) feature and attenuate volume conduction, they are frequently applied as pre-processing methods when computing PLV. However, the effects of spatial filtering on PLV are ambiguous. Therefore, this article aims to explore whether zero-phase PLV is meaningful and how this is influenced by spatial filtering. Based on archival EEG data of left and right hand movement tasks for 32 subjects, we compared BP and PLV feature using data with and without pre-processing by a large Laplacian. Results showed that using ear-referenced data, zero-phase PLV provided unique information independent of BP for task prediction which was not explained by volume conduction and was significantly decreased when a large Laplacian was applied. In other words, the large Laplacian eliminated the useful information in zero-phase PLV for task prediction suggesting that it contains effects of both amplitude and phase. Therefore, zero-phase PLV may have functional significance beyond volume conduction. The interpretation of spatial filtering may be complicated by effects of phase. Copyright © 2017 Elsevier Inc. All rights reserved.

Cardiovascular response to lower body negative pressure stimulation before, during, and after space flight

NASA Technical Reports Server (NTRS)

Baisch, F.; Beck, L.; Blomqvist, G.; Wolfram, G.; Drescher, J.; Rome, J. L.; Drummer, C.

2000-01-01

BACKGROUND: It is well known that space travel cause post-flight orthostatic hypotension and it was assumed that autonomic cardiovascular control deteriorates in space. Lower body negative pressure (LBNP) was used to assess autonomic function of the cardiovascular system. METHODS: LBNP tests were performed on six crew-members before and on the first days post-flight in a series of three space missions. Additionally, two of the subjects performed LBNP tests in-flight. LBNP mimics fluid distribution of upright posture in a gravity independent way. It causes an artificial sequestration of blood, reduces preload, and filtrates plasma into the lower part of the body. Fluid distribution was assessed by bioelectrical impedance and anthropometric measurements. RESULTS: Heart rate, blood pressure, and total peripheral resistance increased significantly during LBNP experiments in-flight. The decrease in stroke volume, the increased pooling of blood, and the increased filtration of plasma into the lower limbs during LBNP indicated that a plasma volume reduction and a deficit of the interstitial volume of lower limbs rather than a change in cardiovascular control was responsible for the in-flight response. Post-flight LBNP showed no signs of cardiovascular deterioration. The still more pronounced haemodynamic changes during LBNP reflected the expected behaviour of cardiovascular control faced with less intravascular volume. In-flight, the status of an intra-and extravascular fluid deficit increases sympathetic activity, the release of vasoactive substances and consequently blood pressure. Post-flight, blood pressure decreases significantly below pre-flight values after restoration of volume deficits. CONCLUSION: We conclude that the cardiovascular changes in-flight are a consequence of a fluid deficit rather than a consequence of changes in autonomic signal processing.

Sympathetic regulation and anterior cingulate cortex volume are altered in a rat model of chronic back pain.

PubMed

Touj, Sara; Houle, Sébastien; Ramla, Djamel; Jeffrey-Gauthier, Renaud; Hotta, Harumi; Bronchti, Gilles; Martinoli, Maria-Grazia; Piché, Mathieu

2017-06-03

Chronic pain is associated with autonomic disturbance. However, specific effects of chronic back pain on sympathetic regulation remain unknown. Chronic pain is also associated with structural changes in the anterior cingulate cortex (ACC), which may be linked to sympathetic dysregulation. The aim of this study was to determine whether sympathetic regulation and ACC surface and volume are affected in a rat model of chronic back pain, in which complete Freund Adjuvant (CFA) is injected in back muscles. Sympathetic regulation was assessed with renal blood flow (RBF) changes induced by electrical stimulation of a hind paw, while ACC structure was examined by measuring cortical surface and volume. RBF changes and ACC volume were compared between control rats and rats injected with CFA in back muscles segmental (T10) to renal sympathetic innervation or not (T2). In rats with CFA, chronic inflammation was observed in the affected muscles in addition to increased nuclear factor-kappa B (NF-kB) protein expression in corresponding spinal cord segments (p=0.01) as well as decreased ACC volume (p<0.05). In addition, intensity-dependent decreases in RBF during hind paw stimulation were attenuated by chronic pain at T2 (p's<0.05) and T10 (p's<0.05), but less so at T10 compared with T2 (p's<0.05). These results indicate that chronic back pain alters sympathetic functions through non-segmental mechanisms, possibly by altering descending regulatory pathways from ACC. Yet, segmental somato-sympathetic reflexes may compete with non-segmental processes depending on the back region affected by pain and according to the segmental organization of the sympathetic nervous system. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Evolution of deep gray matter volume across the human lifespan.

PubMed

Narvacan, Karl; Treit, Sarah; Camicioli, Richard; Martin, Wayne; Beaulieu, Christian

2017-08-01

Magnetic resonance imaging of subcortical gray matter structures, which mediate behavior, cognition and the pathophysiology of several diseases, is crucial for establishing typical maturation patterns across the human lifespan. This single site study examines T1-weighted MPRAGE images of 3 healthy cohorts: (i) a cross-sectional cohort of 406 subjects aged 5-83 years; (ii) a longitudinal neurodevelopment cohort of 84 subjects scanned twice approximately 4 years apart, aged 5-27 years at first scan; and (iii) a longitudinal aging cohort of 55 subjects scanned twice approximately 3 years apart, aged 46-83 years at first scan. First scans from longitudinal subjects were included in the cross-sectional analysis. Age-dependent changes in thalamus, caudate, putamen, globus pallidus, nucleus accumbens, hippocampus, and amygdala volumes were tested with Poisson, quadratic, and linear models in the cross-sectional cohort, and quadratic and linear models in the longitudinal cohorts. Most deep gray matter structures best fit to Poisson regressions in the cross-sectional cohort and quadratic curves in the young longitudinal cohort, whereas the volume of all structures except the caudate and globus pallidus decreased linearly in the longitudinal aging cohort. Males had larger volumes than females for all subcortical structures, but sex differences in trajectories of change with age were not significant. Within subject analysis showed that 65%-80% of 13-17 year olds underwent a longitudinal decrease in volume between scans (∼4 years apart) for the putamen, globus pallidus, and hippocampus, suggesting unique developmental processes during adolescence. This lifespan study of healthy participants will form a basis for comparison to neurological and psychiatric disorders. Hum Brain Mapp 38:3771-3790, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Temporal trends of bulk precipitation and stream water chemistry (1977-1997) in a small forested area, Krusne hory, northern Bohemia, Czech Republic

USGS Publications Warehouse

Peters, N.E.; Cerny, J.; Havel, M.; Krejci, R.

1999-01-01

The Krusne hory (Erzgebirge or Ore Mountains) has been heavily affected by high atmospheric pollutant deposition caused by fossil fuel combustion in an adjacent Tertiary coal basin. Long-term routine sampling of bulk precipitation (1977-1996) and stream water (1977-1998) in a forested area on the south-eastern slope of the mountains were used to evaluate trends and patterns in solute concentration and flux with respect to controlling processes. From 1977 to 1996, the annual volume-weighted Ca2+ and SO42- concentrations decreased in bulk precipitation. However, after 1989, when a pronounced and continuous decrease occurred in coal production, annual volume-weighted concentrations decreased for most solutes, except H+. The concentration decreases were marked, with 1996 levels at or below 50% of those in 1989. The lack of a trend in H+ is attributed to similar decreases in both acid anions and neutralizing base cations. Stream water concentrations of most solutes, i.e. H+, Ca2+, Mg2+, SO42- and NO3-, were highest at the onset of sampling in 1977, decreased markedly from 1977 to 1983 and decreased more gradually from 1983 to 1998. The spruce forest die-back and removal reduced dry deposition of these solutes by reducing the filtering action, which was provided by the forest canopy. A notable decrease in stream water Ca2+ concentrations occurred after 1995 and may be due to the depletion of Ca2+, which was provided by catchment liming in 1986, 1988 and 1989. Solute flux trends in bulk atmospheric deposition and stream water generally were not significant and the lack of trend is attributed to the large interannual variability in precipitation quantity and runoff, respectively. All solutes except Na+ varied seasonally. The average seasonal concentrations varied between the solutes, but for most solutes were highest in winter and spring and lowest in summer, correlating with the seasonal trend and runoff. For Ca2+, Mg2+ and SO42-, the concentration minimum occurs in September and the maximum occurs in February or March, correlating with the seasonal baseflow. These solutes are primarily controlled by the contribution of soil water and groundwater to stream flow. During snowmelt, the meltwater generally causes concentrations to decrease as soil water and groundwater are diluted. For NO3, average minimum concentrations occur in August at the end of the growing season concurrent with the lowest stream flow, and the maximum occurs in February and March with high stream flow during snowmelt. Seasonal stream water NO3- concentration variations are large compared with the long-term decrease.The Krusne hory (Erzgebirge or Ore Mountains) has been heavily affected by high atmospheric pollutant deposition caused by fossil fuel combustion in an adjacent Tertiary coal basin. Long-term routine sampling of bulk precipitation (1977-1996) and stream water (1977-1998) in a forested area on the south-eastern slope of the mountains were used to evaluate trends and patterns in solute concentration and flux with respect to controlling processes. From 1977 to 1996, the annual volume-weighted Ca2+ and SO42- concentrations decreased in bulk precipitation. However, after 1989, when a pronounced and continuous decrease occurred in coal production, annual volume-weighted concentrations decreased for most solutes, except H+. The concentration decreases were marked, with 1996 levels at or below 50% of those in 1989. The lack of a trend in H+ is attributed to similar decreases in both acid anions and neutralizing base cations. Stream water concentrations of most solutes, i.e. H+, Ca2+, Mg2+, SO42- and NO3-, were highest at the onset of sampling in 1977, decreased markedly from 1977 to 1983 and decreased more gradually from 1983 to 1998. The spruce forest die-back and removal reduced dry deposition of these solutes by reducing the filtering action, which was provided by the forest canopy. A notable decrease in stream water Ca2+ concentrations occurred after 1995 an

Improving Butanol Fermentation To Enter the Advanced Biofuel Market

PubMed Central

Tracy, Bryan P.

2012-01-01

ABSTRACT 1-Butanol is a large-volume, intermediate chemical with favorable physical and chemical properties for blending with or directly substituting for gasoline. The per-volume value of butanol, as a chemical, is sufficient for investing into the recommercialization of the classical acetone-butanol-ethanol (ABE) (E. M. Green, Curr. Opin. Biotechnol. 22:337–343, 2011) fermentation process. Furthermore, with modest improvements in three areas of the ABE process, operating costs can be sufficiently decreased to make butanol an economically viable advanced biofuel. The three areas of greatest interest are (i) maximizing yields of butanol on any particular substrate, (ii) expanding substrate utilization capabilities of the host microorganism, and (iii) reducing the energy consumption of the overall production process, in particular the separation and purification operations. In their study in the September/October 2012 issue of mBio, Jang et al. [mBio 3(5):e00314-12, 2012] describe a comprehensive study on driving glucose metabolism in Clostridium acetobutylicum to the production of butanol. Moreover, they execute a metabolic engineering strategy to achieve the highest yet reported yields of butanol on glucose. PMID:23232720

Neurobiological correlates of emotional intelligence in voice and face perception networks

PubMed Central

Karle, Kathrin N; Ethofer, Thomas; Jacob, Heike; Brück, Carolin; Erb, Michael; Lotze, Martin; Nizielski, Sophia; Schütz, Astrid; Wildgruber, Dirk; Kreifelts, Benjamin

2018-01-01

Abstract Facial expressions and voice modulations are among the most important communicational signals to convey emotional information. The ability to correctly interpret this information is highly relevant for successful social interaction and represents an integral component of emotional competencies that have been conceptualized under the term emotional intelligence. Here, we investigated the relationship of emotional intelligence as measured with the Salovey-Caruso-Emotional-Intelligence-Test (MSCEIT) with cerebral voice and face processing using functional and structural magnetic resonance imaging. MSCEIT scores were positively correlated with increased voice-sensitivity and gray matter volume of the insula accompanied by voice-sensitivity enhanced connectivity between the insula and the temporal voice area, indicating generally increased salience of voices. Conversely, in the face processing system, higher MSCEIT scores were associated with decreased face-sensitivity and gray matter volume of the fusiform face area. Taken together, these findings point to an alteration in the balance of cerebral voice and face processing systems in the form of an attenuated face-vs-voice bias as one potential factor underpinning emotional intelligence. PMID:29365199

Neurobiological correlates of emotional intelligence in voice and face perception networks.

PubMed

Karle, Kathrin N; Ethofer, Thomas; Jacob, Heike; Brück, Carolin; Erb, Michael; Lotze, Martin; Nizielski, Sophia; Schütz, Astrid; Wildgruber, Dirk; Kreifelts, Benjamin

2018-02-01

Facial expressions and voice modulations are among the most important communicational signals to convey emotional information. The ability to correctly interpret this information is highly relevant for successful social interaction and represents an integral component of emotional competencies that have been conceptualized under the term emotional intelligence. Here, we investigated the relationship of emotional intelligence as measured with the Salovey-Caruso-Emotional-Intelligence-Test (MSCEIT) with cerebral voice and face processing using functional and structural magnetic resonance imaging. MSCEIT scores were positively correlated with increased voice-sensitivity and gray matter volume of the insula accompanied by voice-sensitivity enhanced connectivity between the insula and the temporal voice area, indicating generally increased salience of voices. Conversely, in the face processing system, higher MSCEIT scores were associated with decreased face-sensitivity and gray matter volume of the fusiform face area. Taken together, these findings point to an alteration in the balance of cerebral voice and face processing systems in the form of an attenuated face-vs-voice bias as one potential factor underpinning emotional intelligence.

High tidal volume decreases adult respiratory distress syndrome, atelectasis, and ventilator days compared with low tidal volume in pediatric burned patients with inhalation injury.

PubMed

Sousse, Linda E; Herndon, David N; Andersen, Clark R; Ali, Arham; Benjamin, Nicole C; Granchi, Thomas; Suman, Oscar E; Mlcak, Ronald P

2015-04-01

Inhalation injury, which is among the causes of acute lung injury and acute respiratory distress syndrome (ARDS), continues to represent a significant source of mortality in burned patients. Inhalation injury often requires mechanical ventilation, but the ideal tidal volume strategy is not clearly defined in burned pediatric patients. The aim of this study was to determine the effects of low and high tidal volume on the number of ventilator days, ventilation pressures, and incidence of atelectasis, pneumonia, and ARDS in pediatric burned patients with inhalation injury within 1 year post burn injury. From 1986 to 2014, inhalation injury was diagnosed by bronchoscopy in pediatric burned patients (n = 932). Patients were divided into 3 groups: unventilated (n = 241), high tidal volume (HTV, 15 ± 3 mL/kg, n = 190), and low tidal volume (LTV, 9 ± 3 mL/kg, n = 501). High tidal volume was associated with significantly decreased ventilator days (p < 0.005) and maximum positive end expiratory pressure (p < 0.0001) and significantly increased maximum peak inspiratory pressure (p < 0.02) and plateau pressure (p < 0.02) compared with those in patients with LTV. The incidence of atelectasis (p < 0.0001) and ARDS (p < 0.02) was significantly decreased with HTV compared with LTV. However, the incidence of pneumothorax was significantly increased in the HTV group compared with the LTV group (p < 0.03). High tidal volume significantly decreases ventilator days and the incidence of both atelectasis and ARDS compared with low tidal volume in pediatric burned patients with inhalation injury. Therefore, the use of HTV may interrupt sequences leading to lung injury in our patient population. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Development of the Cerebral Cortex across Adolescence: A Multisample Study of Inter-Related Longitudinal Changes in Cortical Volume, Surface Area, and Thickness.

PubMed

Tamnes, Christian K; Herting, Megan M; Goddings, Anne-Lise; Meuwese, Rosa; Blakemore, Sarah-Jayne; Dahl, Ronald E; Güroğlu, Berna; Raznahan, Armin; Sowell, Elizabeth R; Crone, Eveline A; Mills, Kathryn L

2017-03-22

Before we can assess and interpret how developmental changes in human brain structure relate to cognition, affect, and motivation, and how these processes are perturbed in clinical or at-risk populations, we must first precisely understand typical brain development and how changes in different structural components relate to each other. We conducted a multisample magnetic resonance imaging study to investigate the development of cortical volume, surface area, and thickness, as well as their inter-relationships, from late childhood to early adulthood (7-29 years) using four separate longitudinal samples including 388 participants and 854 total scans. These independent datasets were processed and quality-controlled using the same methods, but analyzed separately to study the replicability of the results across sample and image-acquisition characteristics. The results consistently showed widespread and regionally variable nonlinear decreases in cortical volume and thickness and comparably smaller steady decreases in surface area. Further, the dominant contributor to cortical volume reductions during adolescence was thinning. Finally, complex regional and topological patterns of associations between changes in surface area and thickness were observed. Positive relationships were seen in sulcal regions in prefrontal and temporal cortices, while negative relationships were seen mainly in gyral regions in more posterior cortices. Collectively, these results help resolve previous inconsistencies regarding the structural development of the cerebral cortex from childhood to adulthood, and provide novel insight into how changes in the different dimensions of the cortex in this period of life are inter-related. SIGNIFICANCE STATEMENT Different measures of brain anatomy develop differently across adolescence. Their precise trajectories and how they relate to each other throughout development are important to know if we are to fully understand both typical development and disorders involving aberrant brain development. However, our understanding of such trajectories and relationships is still incomplete. To provide accurate characterizations of how different measures of cortical structure develop, we performed an MRI investigation across four independent datasets. The most profound anatomical change in the cortex during adolescence was thinning, with the largest decreases observed in the parietal lobe. There were complex regional patterns of associations between changes in surface area and thickness, with positive relationships seen in sulcal regions in prefrontal and temporal cortices, and negative relationships seen mainly in gyral regions in more posterior cortices. Copyright © 2017 Tamnes et al.

Implementation of transcatheter aortic valve replacement in California: Influence on aortic valve surgery.

PubMed

Maximus, Steven; Milliken, Jeffrey C; Danielsen, Beate; Shemin, Richard; Khan, Junaid; Carey, Joseph S

2018-04-01

Transcatheter aortic valve replacement (TAVR) procedures were introduced in 2011. Initially, procedures were limited to patients who were not surgical candidates, but subsequently high-risk surgical candidates were considered for TAVR. The influence on aortic valve surgery in California is unknown. The California Office of Statewide Health Planning and Development hospitalized patient discharge database was queried for the years 2009 through 2014. isolated surgical aortic valve and aortic valve/coronary artery bypass graft (SAVR) and TAVR procedures were identified by International Classification of Diseases-9th revision clinical modification procedure codes. Seven TAVR programs were introduced in 2011, 12 in 2012, 3 in 2013, and 6 in 2014. SAVR procedure volumes were compared from the 2 years before institution with SAVR volumes during the year(s) after institution of the TAVR program in these 28 hospitals. Overall, surgical volumes increased during the first, second, and third years after implementation of TAVR procedures. Among 7 hospitals with 4-year programs, surgical volumes increased to a maximum of 15.5% during the third year, then began to decrease. The hospital performing the largest number of TAVR procedures showed a marked decrease in SAVR volume by the fourth year, suggesting a shift of SAVR candidates to TAVR. Among all hospitals with 4-year programs, TAVR exceeded SAVR procedures by the fourth year. In California overall, SAVR increased during 2011 through 2013, due primarily to increasing volume of isolated SAVR procedures. Statewide, isolated SAVR increased from a yearly average of 3111 procedures during 2009-2010 to 3592 (+15.5%) in 2013, then decreased slightly in 2014. SAVR plus coronary artery bypass graft procedures decreased during the same time period. After implementation of TAVR, hospital SAVR volumes increased moderately, then began to decrease by the fourth year, when TAVR volume exceeded SAVR. Surgical candidates may be identified during evaluation for TAVR, resulting in increased SAVR volume. Increasing SAVR volume may also be related to improved patient and provider awareness of aortic valve disease. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Dodecafluoropentane Emulsion Decreases Infarct Volume in a Rabbit Ischemic Stroke Model

PubMed Central

Culp, William C.; Woods, Sean D.; Skinner, Robert D.; Brown, Aliza T.; Lowery, John D.; Johnson, Jennifer L. H.; Unger, Evan C.; Hennings, Leah J.; Borrelli, Michael J.; Roberson, Paula K.

2011-01-01

Purpose To assess the efficacy of dodecafluoropentane emulsion (DDFPe), a nano droplet emulsion with significant oxygen transport potential, in decreasing infarct volume using an insoluble emboli rabbit stroke model. Methods New Zealand White rabbits (n=64; 5.1±0.50 kg) received angiography and embolic spheres in the internal carotid artery occluding branches. Rabbits were randomly assigned to groups in 4-hour and 7-hour studies. Four-hour groups included: control (n=7, embolized without treatment) or DDFPe treatment 30-min before stroke (n=7), or at stroke onset (n=8), 30-min after stroke (n=5), 1-hour after stroke (n=7), 2-hours after stroke (n=5), or 3-hours after stroke (n=6). Seven-hour groups included control (n=6), DDFPe at 1-hour after stroke (n=8), and DDFPe at 6-hours after stroke (n=5). DDFPe dose was 2% w/v (weight/volume) intravenous injection, 0.6 mL/kg, and repeated every 90 minutes as time allowed. Following euthanasia infarct volume was determined using vital stains on brain sections. Results At 4-hours, median percent infarct volume decreased for all DDFPe treatment times (pre-treatment=0.30%, p=0.004; onset=0.20%, p=0.004; 30-min=0.35%, p=0.009, 1-hour=0.30%, p=0.01, 2-hours=0.40%, p=0.009, 3-hours=0.25%, p=0.003) compared with controls (3.20%). At 7-hours, median percent infarct volume decreased with treatment at 1-hour (0.25%, p=0.007) but not for 6-hours (1.4%, p=0.49) compared with controls (2.2%). Conclusions Intravenous DDFPe in an animal model decreases infarct volumes and protects brain tissue from ischemia justifying further investigation. PMID:22079515

Decreased left hippocampal volumes in parents with or without posttraumatic stress disorder who lost their only child in China.

PubMed

Luo, Yifeng; Shan, Hairong; Liu, Yu; Wu, Liwei; Zhang, Xiaojie; Ma, Tieliang; Zhu, Wenjiao; Yang, Yue; Wang, Jichen; Cao, Zhihong

2016-06-01

Limbic structural changes have been found in people with post-traumatic stress disorder (PTSD). However, the results were controversial, and no study has examined the hippocampal and amygdala volume changes in parents with or without PTSD who had lost their only child and could no longer conceive in China. Hippocampal and amygdala volumes of 57 parents with PTSD (PTSD+), 11 trauma-exposed parents without PTSD (PTSD-) and 39 non-traumatized controls were examined using magnetic resonance imaging. Correlations of the volumes with the time since trauma, Clinician-Administered PTSD Scale (CAPS) scores, age, gender and intracranial volume (ICV) were investigated in the PTSD+ group. left hippocampal volumes were significantly smaller in the PTSD+ and PTSD- groups than in the controls, but there were no significant differences between the PTSD+ and PTSD- groups. Furthermore, there was no significant difference in the right hippocampus or bilateral amygdala volumes. Additionally, the hippocampal and amygdala volumes showed no correlation with the time since trauma, CAPS score and gender, whereas the left hippocampal volumes were correlated with ICV, and the bilateral amygdala volumes were correlated with ICV and age in the PTSD+ group. The PTSD- group included only 11 participants. left hippocampal volumes decreased in parents who lost their only child, with or without PTSD. Our results suggest a potentially unique role of the trauma of losing an only child, which is extremely painful and may induce a decrease in the left hippocampal volume independent of PTSD effects. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of preoperative medications on gastric pH, volume, and flora.

PubMed Central

Laws, H L; Bryant, J W; Palmer, M D; Boudreaux, A M; Donald, J M; Wheeler, A S

1986-01-01

Aspiration of acid gastric juice poses a potential threat during operations. Many anesthesiologists use a variety of agents aimed at decreasing gastric volume and/or acidity. The effect of three agents on gastric volume, pH, and flora, and the effect of cefazolin on gastric flora in morbidly obese patients were studied. Cefazolin did not sterilize the gastric lumen. Almost one-half of patients not treated with an H2 blocker had a pH below 2.5 and a gastric volume of 20 ml or more. Five had both a low pH and significant volume and, thus, the potential for lethal aspiration. Two doses of cimetidine, 300 mgm orally, or of ranitidine, 150 orally, the evening before and the morning of operation decreased gastric volume and raised pH reliably to a level that should be protective from fatal aspiration. However, gastric cultures after these drugs were positive 86% of the time with a larger variety of organisms than in the untreated stomachs. Metoclopramide failed to decrease gastric volume or raise pH. Transoperative cefazolin was used in all patients. Clinical infection was not a problem. PMID:3521506

OCT-based full crystalline lens shape change during accommodation in vivo.

PubMed

Martinez-Enriquez, Eduardo; Pérez-Merino, Pablo; Velasco-Ocana, Miriam; Marcos, Susana

2017-02-01

The full shape of the accommodating crystalline lens was estimated using custom three-dimensional (3-D) spectral OCT and image processing algorithms. Automatic segmentation and distortion correction were used to construct 3-D models of the lens region visible through the pupil. The lens peripheral region was estimated with a trained and validated parametric model. Nineteen young eyes were measured at 0-6 D accommodative demands in 1.5 D steps. Lens volume, surface area, diameter, and equatorial plane position were automatically quantified. Lens diameter & surface area correlated negatively and equatorial plane position positively with accommodation response. Lens volume remained constant and surface area decreased with accommodation, indicating that the lens material is incompressible and the capsular bag elastic.

Flight Weight Design Nickel-Hydrogen Cells Using Lightweight Nickel Fiber Electrodes

NASA Technical Reports Server (NTRS)

Britton, Doris L.; Willis, Bob; Pickett, David F.

2003-01-01

The goal of this program is to develop a lightweight nickel electrode for advanced aerospace nickel-hydrogen cells and batteries with improved specific energy and specific volume. The lightweight nickel electrode will improve the specific energy of a nickel-hydrogen cell by >50%. These near-term advanced batteries will reduce power system mass and volume, while decreasing the cost, thus increasing mission capabilities and enabling small spacecraft missions. This development also offers a cost savings over the traditional sinter development methods for fabrication. The technology has been transferred to Eagle-Picher, a major aerospace battery manufacturer, who has scaled up the process developed at NASA GRC and fabricated electrodes for incorporation into flight-weight nickel-hydrogen cells.

Membrane treatment of liquid wastes from radiological decontamination operations.

PubMed

Svittsov, A A; Khubetsov, S B; Volchek, K

2011-01-01

The paper focuses on the evaluation of membrane filtration for the treatment of liquid radioactive streams generated in area decontamination operations. In this work, semi-permeable membranes were demonstrated to be effective reducing the volume of wastewater containing cesium and cobalt by two orders of a magnitude. The efficiency of membrane separation was enhanced by employing additives that enlarged the size of target radionuclide species and improved their rejection by the membranes. This was achieved by chelation with synthetic water-soluble polymers and by adsorption on micro particles of adsorbent coupled with micelle formation. The effect of wastewater composition and that of the radionuclide-binding additives on the volume reduction was investigated. Membrane treatment is expected to help simplify further processing and decrease disposal costs.

OCT-based full crystalline lens shape change during accommodation in vivo

PubMed Central

Martinez-Enriquez, Eduardo; Pérez-Merino, Pablo; Velasco-Ocana, Miriam; Marcos, Susana

2017-01-01

The full shape of the accommodating crystalline lens was estimated using custom three-dimensional (3-D) spectral OCT and image processing algorithms. Automatic segmentation and distortion correction were used to construct 3-D models of the lens region visible through the pupil. The lens peripheral region was estimated with a trained and validated parametric model. Nineteen young eyes were measured at 0-6 D accommodative demands in 1.5 D steps. Lens volume, surface area, diameter, and equatorial plane position were automatically quantified. Lens diameter & surface area correlated negatively and equatorial plane position positively with accommodation response. Lens volume remained constant and surface area decreased with accommodation, indicating that the lens material is incompressible and the capsular bag elastic. PMID:28270993

Changes in Search Path Complexity and Length During Learning of a Virtual Water Maze: Age Differences and Differential Associations with Hippocampal Subfield Volumes

PubMed Central

Daugherty, Ana M.; Bender, Andrew R.; Yuan, Peng; Raz, Naftali

2016-01-01

Impairment of hippocampus-dependent cognitive processes has been proposed to underlie age-related deficits in navigation. Animal studies suggest a differential role of hippocampal subfields in various aspects of navigation, but that hypothesis has not been tested in humans. In this study, we examined the association between volume of hippocampal subfields and age differences in virtual spatial navigation. In a sample of 65 healthy adults (age 19–75 years), advanced age was associated with a slower rate of improvement operationalized as shortening of the search path over 25 learning trials on a virtual Morris water maze task. The deficits were partially explained by greater complexity of older adults' search paths. Larger subiculum and entorhinal cortex volumes were associated with a faster decrease in search path complexity, which in turn explained faster shortening of search distance. Larger Cornu Ammonis (CA)1–2 volume was associated with faster distance shortening, but not in path complexity reduction. Age differences in regional volumes collectively accounted for 23% of the age-related variance in navigation learning. Independent of subfield volumes, advanced age was associated with poorer performance across all trials, even after reaching the asymptote. Thus, subiculum and CA1–2 volumes were associated with speed of acquisition, but not magnitude of gains in virtual maze navigation. PMID:25838036

Three-dimensional confocal morphometry – a new approach for studying dynamic changes in cell morphology in brain slices

PubMed Central

Chvátal, Alexandr; Anděrová, Miroslava; Kirchhoff, Frank

2007-01-01

Pathological states in the central nervous system lead to dramatic changes in the activity of neuroactive substances in the extracellular space, to changes in ionic homeostasis and often to cell swelling. To quantify changes in cell morphology over a certain period of time, we employed a new technique, three-dimensional confocal morphometry. In our experiments, performed on enhanced green fluorescent protein/glial fibrillary acidic protein astrocytes in brain slices in situ and thus preserving the extracellular microenvironment, confocal morphometry revealed that the application of hypotonic solution evoked two types of volume change. In one population of astrocytes, hypotonic stress evoked small cell volume changes followed by a regulatory volume decrease, while in the second population volume changes were significantly larger without subsequent volume regulation. Three-dimensional cell reconstruction revealed that even though the total astrocyte volume increased during hypotonic stress, the morphological changes in various cell compartments and processes were more complex than have been previously shown, including swelling, shrinking and structural rearrangement. Our data show that astrocytes in brain slices in situ during hypotonic stress display complex behaviour. One population of astrocytes is highly capable of cell volume regulation, while the second population is characterized by prominent cell swelling, accompanied by plastic changes in morphology. It is possible to speculate that these two astrocyte populations play different roles during physiological and pathological states. PMID:17488344

Feasibility study of an Integrated Program for Aerospace vehicle Design (IPAD). Volume 1A: Summary

NASA Technical Reports Server (NTRS)

Miller, R. E., Jr.; Redhed, D. D.; Kawaguchi, A. S.; Hansen, S. D.; Southall, J. W.

1973-01-01

IPAD was defined as a total system oriented to the product design process. This total system was designed to recognize the product design process, individuals and their design process tasks, and the computer-based IPAD System to aid product design. Principal elements of the IPAD System include the host computer and its interactive system software, new executive and data management software, and an open-ended IPAD library of technical programs to match the intended product design process. The basic goal of the IPAD total system is to increase the productivity of the product design organization. Increases in individual productivity were feasible through automation and computer support of routine information handling. Such proven automation can directly decrease cost and flowtime in the product design process.

Capillary forces exerted by liquid drops caught between crossed cylinders. A 3-D meniscus problem with free contact line

NASA Technical Reports Server (NTRS)

Patzek, T. W.; Scriven, L. E.

1982-01-01

The Young-Laplace equation is solved for three-dimensional menisci between crossed cylinders, with either the contact line fixed or the contact angle prescribed, by means of the Galerkin/finite element method. Shapes are computed, and with them the practically important quantities: drop volume, wetted area, capillary pressure force, surface tension force, and the total force exerted by the drop on each cylinder. The results show that total capillary force between cylinders increases with decreasing contact angle, i.e. with better wetting. Capillary force is also increases with decreasing drop volume, approaching an asymptotic limit. However, the wetted area on each cylinder decreases with decreasing drop volume, which raises the question of the optimum drop volume to strive for, when permanent bonding is sought from solidified liquid. For then the strength of the bond is likely to depend upon the area of contact, which is the wetted area when the bonding agent was introduced in liquid form.

Characteristics, changes and influence of body composition during a 4486 km transcontinental ultramarathon: results from the Transeurope Footrace mobile whole body MRI-project

PubMed Central

2013-01-01

Background Almost nothing is known about the medical aspects of runners doing a transcontinental ultramarathon over several weeks. The results of differentiated measurements of changes in body composition during the Transeurope Footrace 2009 using a mobile whole body magnetic resonance (MR) imager are presented and the proposed influence of visceral and somatic adipose and lean tissue distribution on performance tested. Methods 22 participants were randomly selected for the repeated MR measurements (intervals: 800 km) with a 1.5 Tesla MR scanner mounted on a mobile unit during the 64-stage 4,486 km ultramarathon. A standardized and validated MRI protocol was used: T1 weighted turbo spin echo sequence, echo time 12 ms, repetition time 490 ms, slice thickness 10 mm, slice distance 10 mm (breath holding examinations). For topographic tissue segmentation and mapping a modified fuzzy c-means algorithm was used. A semi-automatic post-processing of whole body MRI data sets allows reliable analysis of the following body tissue compartments: Total body volume (TV), total somatic (TSV) and total visceral volume (TVV), total adipose (TAT) and total lean tissue (TLT), somatic (SLT) and visceral lean tissue (VLT), somatic (SAT) and visceral adipose tissue (VAT) and somatic adipose soft tissue (SAST). Specific volume changes were tested on significance. Tests on difference and relationship regarding prerace and race performance and non-finishing were done using statistical software SPSS. Results Total, somatic and visceral volumes showed a significant decrease throughout the race. Adipose tissue showed a significant decrease compared to the start at all measurement times for TAT, SAST and VAT. Lean adipose tissues decreased until the end of the race, but not significantly. The mean relative volume changes of the different tissue compartments at the last measurement compared to the start were: TV −9.5% (SE 1.5%), TSV −9.4% (SE 1.5%), TVV −10.0% (SE 1.4%), TAT −41.3% (SE 2.3%), SAST −48.7% (SE 2.8%), VAT −64.5% (SE 4.6%), intraabdominal adipose tissue (IAAT) −67.3% (SE 4.3%), mediastinal adopose tissue (MAT) −41.5% (SE 7.1%), TLT −1.2% (SE 1.0%), SLT −1.4% (SE 1.1%). Before the start and during the early phase of the Transeurope Footrace 2009, the non-finisher group had a significantly higher percentage volume of TVV, TAT, SAST and VAT compared to the finisher group. VAT correlates significantly with prerace training volume and intensity one year before the race and with 50 km- and 24 hour-race records. Neither prerace body composition nor specific tissue compartment volume changes showed a significant relationship to performance in the last two thirds of the Transeurope Footrace 2009. Conclusions With this mobile MRI field study the complex changes in body composition during a multistage ultramarathon could be demonstrated in detail in a new and differentiated way. Participants lost more than half of their adipose tissue. Even lean tissue volume (mainly skeletal muscle tissue) decreased due to the unpreventable chronic negative energy balance during the race. VAT has the fastest and highest decrease compared to SAST and lean tissue compartments during the race. It seems to be the most sensitive morphometric parameter regarding the risk of non-finishing a transcontinental footrace and shows a direct relationship to prerace-performance. However, body volume or body mass and, therefore, fat volume has no correlation with total race performances of ultra-athletes finishing a 4,500 km multistage race. PMID:23657091

Towards a unified analysis of brain maturation and aging across the entire lifespan: A MRI analysis.

PubMed

Coupé, Pierrick; Catheline, Gwenaelle; Lanuza, Enrique; Manjón, José Vicente

2017-11-01

There is no consensus in literature about lifespan brain maturation and senescence, mainly because previous lifespan studies have been performed on restricted age periods and/or with a limited number of scans, making results instable and their comparison very difficult. Moreover, the use of nonharmonized tools and different volumetric measurements lead to a great discrepancy in reported results. Thanks to the new paradigm of BigData sharing in neuroimaging and the last advances in image processing enabling to process baby as well as elderly scans with the same tool, new insights on brain maturation and aging can be obtained. This study presents brain volume trajectory over the entire lifespan using the largest age range to date (from few months of life to elderly) and one of the largest number of subjects (N = 2,944). First, we found that white matter trajectory based on absolute and normalized volumes follows an inverted U-shape with a maturation peak around middle life. Second, we found that from 1 to 8-10 y there is an absolute gray matter (GM) increase related to body growth followed by a GM decrease. However, when normalized volumes were considered, GM continuously decreases all along the life. Finally, we found that this observation holds for almost all the considered subcortical structures except for amygdala which is rather stable and hippocampus which exhibits an inverted U-shape with a longer maturation period. By revealing the entire brain trajectory picture, a consensus can be drawn since most of the previously discussed discrepancies can be explained. Hum Brain Mapp 38:5501-5518, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Pressure-volume relations and bulk modulus under pressure of tetrahedral compounds

NASA Astrophysics Data System (ADS)

Soma, T.; Takahashi, Y.; Kagaya, H.-M.

1985-03-01

The pressure-volume relation and the compression effect on the bulk modulus of tetrahedral compounds such as GaP, InP, ZnS, ZnSe, ZnTe and CdTe are investigated from the electronic theory of solids by using a recently presented binding force, which includes mainly covalent interactions in the pseudopotential formalism and partially ionic interactions. The calculated results of the pressure-volume relations involving the pressure-induced phase transition are useful when comparing with the experimental data under high pressure. The calculated bulk modulus of these compounds increases as the crystal volume decreases. Further, the pressure derivative of bulk modulus is not constant and decreases with the reduction of the crystal volume.

[Function in patients with chronic fibrocavernous tuberculosis].

PubMed

Nefedov, V B; Popova, L A; Shergina, E A

2008-01-01

Vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/VC%, PEF, MEF25, MEF50, MEF75, TLC, TGV, residual volume (RV), R(aw), R(in), R(ex), DLCO-SB, DLCO-SS, PaO2, and PaCO2 were determined in 62 patients with chronic fibrocavernous tuberculosis. Lung dysfunctions were detected in 96.8% of the patients. Changes in lung volumes and capacities were found in 90.3%, impaired bronchial patency was in 90.3%, and pulmonary gas exchange dysfunction was in 79.0%. The lung volume and capacity changes appeared as decreased VC and FVC, decreased and increased TLC, TGV, RV; impaired bronchial patency presented as decreased PEF, MEF25, MEF50, MEF75, and FEV1/VC%; and increased R(aw), R(in), R(ex); pulmonary gas exchange dysfunction manifested itself as reduced DLCO-SB, DLCO-SS, PaO2, and decreased and increased PaCO2. The magnitude of the observed functional changes ranges from slight to significant and drastic with a predominance of considerable and drastic changes in lung volumes and capacities and mild impairments of bronchial patency and pulmonary gas exchange function.

Each procedure matters: threshold for surgeon volume to minimize complications and decrease cost associated with adrenalectomy.

PubMed

Anderson, Kevin L; Thomas, Samantha M; Adam, Mohamed A; Pontius, Lauren N; Stang, Michael T; Scheri, Randall P; Roman, Sanziana A; Sosa, Julie A

2018-01-01

An association has been suggested between increasing surgeon volume and improved patient outcomes, but a threshold has not been defined for what constitutes a "high-volume" adrenal surgeon. Adult patients who underwent adrenalectomy by an identifiable surgeon between 1998-2009 were selected from the Healthcare Cost and Utilization Project National Inpatient Sample. Logistic regression modeling with restricted cubic splines was utilized to estimate the association between annual surgeon volume and complication rates in order to identify a volume threshold. A total of 3,496 surgeons performed adrenalectomies on 6,712 patients; median annual surgeon volume was 1 case. After adjustment, the likelihood of experiencing a complication decreased with increasing annual surgeon volume up to 5.6 cases (95% confidence interval, 3.27-5.96). After adjustment, patients undergoing resection by low-volume surgeons (<6 cases/year) were more likely to experience complications (odds ratio 1.71, 95% confidence interval, 1.27-2.31, P = .005), have a greater hospital stay (relative risk 1.46, 95% confidence interval, 1.25-1.70, P = .003), and at increased cost (+26.2%, 95% confidence interval, 12.6-39.9, P = .02). This study suggests that an annual threshold of surgeon volume (≥6 cases/year) that is associated with improved patient outcomes and decreased hospital cost. This volume threshold has implications for quality improvement, surgical referral and reimbursement, and surgical training. Copyright © 2017 Elsevier Inc. All rights reserved.

Preservation of hippocampal neuron numbers and hippocampal subfield volumes in behaviorally characterized aged tree shrews.

PubMed

Keuker, Jeanine I H; de Biurrun, Gabriel; Luiten, Paul G M; Fuchs, Eberhard

2004-01-19

Aging is associated with a decreased ability to store and retrieve information. The hippocampal formation plays a critical role in such memory processes, and its integrity is affected during normal aging. We used tree shrews (Tupaia belangeri) as an animal model of aging, because in many characteristics, tree shrews are closer to primates than they are to rodents. Young and aged male tree shrews performed a holeboard spatial memory task, which permits assessment of reference and working memory. Upon completion of the behavioral measurements, we carried out modified stereological analyses of neuronal numbers in various subdivisions of the hippocampus and used the Cavalieri method to calculate the volumes of these subfields. Results showed that the working memory of aged tree shrews was significantly impaired compared with that of young animals, whereas the hippocampus-dependent reference memory remained unchanged by aging. Estimation of the number of neurons revealed preserved neuron numbers in the subiculum, in the subregions CA1, CA2, CA3, and in the hilus of the dentate gyrus. Volume measurements showed no aging-related changes in the volume of any of these hippocampal subregions, or in the molecular and granule cell layers of the dentate gyrus of tree shrews. We conclude that the observed changes in memory performance in aging tree shrews are not accompanied by observable reductions of hippocampal neuron numbers or hippocampal volume, rather, the changes in memory performance are more likely the result of modified subcellular mechanisms that are affected by the aging process. Copyright 2003 Wiley-Liss, Inc.

Decreasing trends of suspended particulate matter and PM2.5 concentrations in Tokyo, 1990-2010.

PubMed

Hara, Kunio; Homma, Junichi; Tamura, Kenji; Inoue, Mariko; Karita, Kanae; Yano, Eiji

2013-06-01

In Tokyo, the annual average suspended particulate matter (SPM) and PM2.5 concentrations have decreased in the past two decades. The present study quantitatively evaluated these decreasing trends using data from air-pollution monitoring stations. Annual SPM and PM2.5 levels at 83 monitoring stations and hourly SPM and PM2.5 levels at four monitoring stations in Tokyo, operated by the Tokyo Metropolitan Government, were used for analysis, together with levels of co-pollutants and meteorological conditions. Traffic volume in Tokyo was calculated from the total traveling distance of vehicles as reported by the Ministry of Land, Infrastructure, Transport, and Tourism. High positive correlations between SPM levels and nitrogen oxide levels, sulfur dioxide levels, and traffic volume were determined. The annual average SPM concentration declined by 62.6%from 59.4 microg/m3 in 1994 to 22.2 microg/m3 in 2010, and PM2.5 concentration also declined by 49.8% from 29.3 microg/m3 in 2001 to 14.7 microg/m3 in 2010. Likewise, the frequencies of hourly average SPM and PM2.5 concentrations exceeding the daily guideline values have significantly decreased since 2001 and the hourly average SPM or PM2.5 concentrations per traffic volume for each time period have also significantly decreased since 2001. However SPM and PM2.5 concentrations increased at some monitoring stations between 2004 and 2006 and from 2009 despite strengthened environmental regulations and improvements in vehicle engine performance. The annual average SPM and PM2.5 concentrations were positively correlated with traffic volumes and in particular with the volume of diesel trucks. These results suggest that the decreasing levels of SPM and PM2.5 in Tokyo may be attributable to decreased traffic volumes, along with the effects of stricter governmental regulation and improvements to vehicle engine performance, including the fitting of devices for exhaust emission reduction.

Cell volume changes regulate slick (Slo2.1), but not slack (Slo2.2) K+ channels.

PubMed

Tejada, Maria A; Stople, Kathleen; Hammami Bomholtz, Sofia; Meinild, Anne-Kristine; Poulsen, Asser Nyander; Klaerke, Dan A

2014-01-01

Slick (Slo2.1) and Slack (Slo2.2) channels belong to the family of high-conductance K+ channels and have been found widely distributed in the CNS. Both channels are activated by Na+ and Cl- and, in addition, Slick channels are regulated by ATP. Therefore, the roles of these channels in regulation of cell excitability as well as ion transport processes, like regulation of cell volume, have been hypothesized. It is the aim of this work to evaluate the sensitivity of Slick and Slack channels to small, fast changes in cell volume and to explore mechanisms, which may explain this type of regulation. For this purpose Slick and Slack channels were co-expressed with aquaporin 1 in Xenopus laevis oocytes and cell volume changes of around 5% were induced by exposure to hypotonic or hypertonic media. Whole-cell currents were measured by two electrode voltage clamp. Our results show that Slick channels are dramatically stimulated (196% of control) by cell swelling and inhibited (57% of control) by a decrease in cell volume. In contrast, Slack channels are totally insensitive to similar cell volume changes. The mechanism underlining the strong volume sensitivity of Slick channels needs to be further explored, however we were able to show that it does not depend on an intact actin cytoskeleton, ATP release or vesicle fusion. In conclusion, Slick channels, in contrast to the similar Slack channels, are the only high-conductance K+ channels strongly sensitive to small changes in cell volume.

Estimation of volume and mass and of changes in volume and mass of selected chat piles in the Picher mining district, Ottawa County, Oklahoma, 2005-10

USGS Publications Warehouse

Smith, S. Jerrod

2013-01-01

From the 1890s through the 1970s the Picher mining district in northeastern Ottawa County, Oklahoma, was the site of mining and processing of lead and zinc ore. When mining ceased in about 1979, as much as 165–300 million tons of mine tailings, locally referred to as “chat,” remained in the Picher mining district. Since 1979, some chat piles have been mined for aggregate materials and have decreased in volume and mass. Currently (2013), the land surface in the Picher mining district is covered by thousands of acres of chat, much of which remains on Indian trust land owned by allottees. The Bureau of Indian Affairs manages these allotted lands and oversees the sale and removal of chat from these properties. To help the Bureau of Indian Affairs better manage the sale and removal of chat, the U.S. Geological Survey, in cooperation with the Bureau of Indian Affairs, estimated the 2005 and 2010 volumes and masses of selected chat piles remaining on allotted lands in the Picher mining district. The U.S. Geological Survey also estimated the changes in volume and mass of these chat piles for the period 2005 through 2010. The 2005 and 2010 chat-pile volume and mass estimates were computed for 34 selected chat piles on 16 properties in the study area. All computations of volume and mass were performed on individual chat piles and on groups of chat piles in the same property. The Sooner property had the greatest estimated volume (4.644 million cubic yards) and mass (5.253 ± 0.473 million tons) of chat in 2010. Five of the selected properties (Sooner, Western, Lawyers, Skelton, and St. Joe) contained estimated chat volumes exceeding 1 million cubic yards and estimated chat masses exceeding 1 million tons in 2010. Four of the selected properties (Lucky Bill Humbah, Ta Mee Heh, Bird Dog, and St. Louis No. 6) contained estimated chat volumes of less than 0.1 million cubic yards and estimated chat masses of less than 0.1 million tons in 2010. The total volume of all selected chat piles was estimated to be 18.073 million cubic yards in 2005 and 16.171 million cubic yards in 2010. The total mass of all selected chat piles was estimated to be 20.445 ± 1.840 million tons in 2005 and 18.294 ± 1.646 million tons in 2010. All of the selected chat piles decreased in volume and mass for the period 2005 through 2010. Chat piles CP022 (Ottawa property) and CP013 (Sooner property) had some within-property chat-pile redistribution, with both chat piles having net decreases in volume and mass for the period 2005 through 2010. The Sooner property and the St. Joe property had the greatest volume (and mass) changes, with 1.266 million cubic yards and 0.217 million cubic yards (1.432 ± 0.129 million tons and 0.246 ± 0.022 million tons) of chat being removed, respectively. The chat removed from the Sooner and St. Joe properties accounts for about 78 percent of the chat removed from all selected chat piles and properties. The total volume and mass removed from all selected chat piles for the period 2005 through 2010 were estimated to be 1.902 million cubic yards and 2.151 ± 0.194 million tons, respectively.

Plasma clots gelled by different amounts of calcium for stem cell delivery.

PubMed

Gessmann, Jan; Seybold, Dominik; Peter, Elvira; Schildhauer, Thomas Armin; Köller, Manfred

2013-01-01

Freshly prepared autologous plasma clots may serve as a carrier matrix for expanded multipotent mesenchymal stromal cells (MSCs) or bone marrow cells. By varying the calcium concentration, plasma clots with different properties can be produced. The purpose of this in vitro study was to determine the optimal calcium concentrations for the clotting process, intra-clot cell viability, and clot lysis. Different plasma clots were prepared by adding an equal volume of RPMI1640 (with or without MSCs) to citrate plasma (either containing platelets or platelet-free). Clotting was initiated by the addition of CaCl(2) (10 g/100 ml H(2)O, 10 % solution). The final concentration of CaCl(2) ranged from 1 to 10 % by volume of plasma. Viability and distribution of the MSCs were analysed by calcein-AM/propidium iodide staining. MSC-embedded plasma clots were dissolved with trypsin (0.25 %), and recovered cells were further incubated for 1 week under cell culture conditions. The viability of MSCs embedded in clots formed by the addition of 1-8 % by volume CaCl2 was not affected by incubation of up to 1 week. In contrast, clots produced by higher volumes of CaCl(2) solutions (9-10 % by volume of plasma) showed decreased numbers of viable cells. Intra-clot cell proliferation was highest in clots produced by addition of 5 % CaCl(2) by plasma volume. Osteocalcin release was not influenced in platelet-free plasma but decreased in platelet-containing plasma. Morphological analysis of stained recovered MSCs revealed that lysis of the plasma clot did not affect cell morphology or subsequent spontaneous proliferation. Clot formation and clot stability can be controlled by changing the concentration of CaCl(2) added to plasma. The addition of 5 % CaCl(2) produced a plasma clot with optimal results for stem cell delivery.

Process evaluation of enzymatic hydrolysis with filtrate recycle for the production of high concentration sugars.

PubMed

Xue, Ying; Rusli, Jannov; Chang, Hou-Min; Phillips, Richard; Jameel, Hasan

2012-02-01

Process simulation and lab trials were carried out to demonstrate and confirm the efficiency of the concept that recycling hydrolysate at low total solid enzymatic hydrolysis is one of the options to increase the sugar concentration without mixing problems. Higher sugar concentration can reduce the capital cost for fermentation and distillation because of smaller retention volume. Meanwhile, operation cost will also decrease for less operating volume and less energy required for distillation. With the computer simulation, time and efforts can be saved to achieve the steady state of recycling process, which is the scenario for industrial production. This paper, to the best of our knowledge, is the first paper discussing steady-state saccharification with recycling of the filtrate form enzymatic hydrolysis to increase sugar concentration. Recycled enzymes in the filtrate (15-30% of the original enzyme loading) resulted in 5-10% higher carbohydrate conversion compared to the case in which recycled enzymes were denatured. The recycled hydrolysate yielded 10% higher carbohydrate conversion compared to pure sugar simulated hydrolysate at the same enzyme loading, which indicated hydrolysis by-products could boost enzymatic hydrolysis. The high sugar concentration (pure sugar simulated) showed inhibition effect, since about 15% decrease in carbohydrate conversion was observed compared with the case with no sugar added. The overall effect of hydrolysate recycling at WinGEMS simulated steady-state conditions with 5% total solids was increasing the sugar concentration from 35 to 141 g/l, while the carbohydrate conversion was 2% higher for recycling at steady state (87%) compared with no recycling strategy (85%). Ten percent and 15% total solid processes were also evaluated in this study.

Experimental replacement of calcium carbonates by fluorite: high volume changes and porosity generation

NASA Astrophysics Data System (ADS)

Trindade Pedrosa, Elisabete; Putnis, Andrew

2015-04-01

Pseudomorphic mineral replacement reactions are a common phenomena in nature, and often described as interface-coupled dissolution-reprecipitation processes. The generation of porosity is a key factor for its progression since it creates the pathway for fluid infiltration towards an ongoing reaction front. The generation of porosity depends on two key factors: the molar volume differences between parent and product phase, and the relative solubilities of the parent and product in the fluid at the mineral-fluid interface (Pollok et al., 2011). Jamtveit et al., (2009) demonstrated that the permeability of the parent rock may also be enhanced by the development of fractures as a response to stresses generated by local volume changes at the reaction interface, which in turn increases the reaction rate. The replacement of calcite (CaCO3) by fluorite (CaF2) involves a molar volume decrease of 33.5 %. If indeed high volume changes generate high local stresses, a fragmentation process is expected to be driven by this replacement reaction. To test this hypothesis, a number of hydrothermal experiments were performed. Small cubes of calcite rock (Carrara marble), and single crystals of calcite were used as parent materials. Two fluoride solutions (ammonium fluoride and sodium fluoride) were used as reactants. Samples were reacted at temperatures up to 200°C for various times and quenched to room temperature. After drying, samples were mounted in epoxy holders, cross sections through the centre of the samples were cut and polished, and analysed using scanning electron microscopy (SEM), X-ray diffraction (XRD), and electron microprobe analysis (EMP). The replacement end product of all experiments was confirmed to be fluorite. In every case the external shape of the samples was perfectly maintained. No reaction induced fracturing was visible in any of the samples (rock or single crystals) although the texture of the replaced material was quite complex, often with a 'V' shaped reaction front. The main difference between single crystals and rock was that in the former, grain boundaries were rapid transport pathways for fluid infiltration resulting in the precipitation of fluorite within the sample at locations further from the main reaction front. The porosity formed was very high and complex, its texture depending on the shape and orientation of the replaced material. Very large hollow spaces with diameter >30 μm formed in several samples. In this system the large volume decrease is accommodated by a high porosity rather than fracturing. Jamtveit B., Putnis C.V. & Malthe-Sørenssen A. (2009). Reaction induced fracturing during replacement processes. Contrib. Min. Pet., 157 127-133 Pollok K., Putnis C.V. & Putnis A. (2011) Mineral replacement reactions in solid solution-aqueous solution systems: Volume changes, reaction paths and end points using the example of model salt systems. Am. J. Sci., 311, 211-236

Stress, Aging and Thirst

NASA Technical Reports Server (NTRS)

Greenleaf, John E.

1998-01-01

After growth during adolesence, total body water decreases progressively with aging from 65% of body weight to about 53% of body weight in the 70th decade; a majority of the loss occurs from the extracellular volume, from 42% to about 25%, respectively. Cellular volume also reaches equilibrium in the 70th decade at about 25% of body weight. Various stresses such as exercise, heat and attitude exposure, ad prior dehydration attenuate voluntary fluid intake (involuntary dehydration). Voluntary fluid intake appears to decrease with aging (involuntary dehydration in this sense aging can be considered as a stress. Kidney function and muscle mass (80% water) decrease somewhat with aging, and voluntary fluid intake (thirst) is also attenuated. Thirst is stimulated by increasing osmolality (hypernatremia) of the extracellular fluid and by decreased extracellular volume (mainly plasma volume) which act to increase intracellular fluid volume osmolality to activiate drinking. The latter decreases fluid compartment osmolality which ' It terminates drinking. However, this drinking mechanism seems to be attenuated with aging such that increasing plasma osmolality no longer stimulates fluid intake appropriately. Hypernatremia in the elderly has been associated all too frequently with greater incidence of bacterial infection and increased mortality. Involuntary dehydration can be overcome in young men by acclimation to an intermittent exercise-in-heat training program. Perhaps exercise training in the elderly would also increase voluntary fluid intake and increase muscle mass to enhance retention of water.

Water-quality characteristics in runoff for three discovery farms in North Dakota, 2008-12

USGS Publications Warehouse

Nustad, Rochelle A.; Rowland, Kathleen M.; Wiederholt, Ronald

2015-01-01

Consistent patterns in water quality emerged at each individual farm, but similarities among farms also were observed. Suspended sediment, total phosphorus, and ammonia concentrations generally decreased downstream from feeding areas, and were primarily affected by surface runoff processes such as dilution, settling out of sediment, or vegetative uptake. Because surface runoff affects these constituents, increased annual surface runoff volume tended to result in increased loads and yields. No significant change in nitrate plus nitrite concentration were observed downstream from feeding areas because additional processes such as high solubility, nitrification, denitrification, and surface-groundwater interaction affect nitrate plus nitrite. For nitrate plus nitrite, increases in annual runoff volume did not consistently relate to increases in annual loads and yields. It seems that temporal distribution of precipitation and surface-groundwater interaction affected nitrate plus nitrite loads and yields. For surface drainage sites, the primary form of nitrogen was organic nitrogen whereas for subsurface drainage sites, the primary form of nitrogen was nitrate plus nitrite nitrogen.

Effect of processing parameters and pore structure of nanostructured silica aerogel on the physical properties of aerogel blankets

NASA Astrophysics Data System (ADS)

Latifi, Fatemeh; Talebi, Zahra; Khalili, Haleh; Zarrebini, Mohammad

2018-05-01

This work investigates the influence of processing parameters and aerogel pore structure on the physical properties and hydrophobicity of aerogel blankets. Aerogel blankets were produced by in situ synthesis of nanostructured silica aerogel on a polyester nonwoven substrate. Nitrogen adsorption-desorption analysis, contact angle test and FE-SEM images were used to characterize both the aerogel particles and the blankets. The results showed that the weight and thickness of the blanket were reduced when the low amount of catalyst was used. A decrease in the aerogel pore size from 22 to 11 nm increased the weight and thickness of the blankets. The xerogel particles with high density and pore size of 5 nm reduced the blanket weight. Also, the blanket weight and thickness were increased due to increasing the sol volume. It was found that the hydrophobicity of aerogel blankets is not influenced by sol volume and pore structure of silica aerogel.

SSUSI-Lite: a far-ultraviolet hyper-spectral imager for space weather remote sensing

NASA Astrophysics Data System (ADS)

Ogorzalek, Bernard; Osterman, Steven; Carlsson, Uno; Grey, Matthew; Hicks, John; Hourani, Ramsey; Kerem, Samuel; Marcotte, Kathryn; Parker, Charles; Paxton, Larry J.

2015-09-01

SSUSI-Lite is a far-ultraviolet (115-180nm) hyperspectral imager for monitoring space weather. The SSUSI and GUVI sensors, its predecessors, have demonstrated their value as space weather monitors. SSUSI-Lite is a refresh of the Special Sensor Ultraviolet Spectrographic Imager (SSUSI) design that has flown on the Defense Meteorological Satellite Program (DMSP) spacecraft F16 through F19. The refresh updates the 25-year-old design and insures that the next generation of SSUSI/GUVI sensors can be accommodated on any number of potential platforms. SSUSI-Lite maintains the same optical layout as SSUSI, includes updates to key functional elements, and reduces the sensor volume, mass, and power requirements. SSUSI-Lite contains an improved scanner design that results in precise mirror pointing and allows for variable scan profiles. The detector electronics have been redesigned to employ all digital pulse processing. The largest decrease in volume, mass, and power has been obtained by consolidating all control and power electronics into one data processing unit.

Characterization of biochars derived from agriculture wastes and their adsorptive removal of atrazine from aqueous solution: A comparative study.

PubMed

Liu, Na; Charrua, Alberto Bento; Weng, Chih-Huang; Yuan, Xiaoling; Ding, Feng

2015-12-01

The physicochemical properties of biochars produced from soybeans (SBB), corn stalks (CSB), rice stalks (RSB), poultry manure (PMB), cattle manure (CMB), and pig manure (PgMB) and their adsorption characteristics of atrazine were investigated. The adsorption capacity increased with the increase of temperature and initial atrazine concentration. More atrazine was removed from basic solutions than acidic solutions, due to the effects of adsorption and hydrolysis. The Freundlich isotherm adsorption parameters indicated that the adsorption capacity decreased in the order SBB>RSB>CMB>CSB>PMB>PgMB, which is associated to the pore volume of biochars. The total pore volume and biochar pH were concluded to play important roles in determining the adsorption capacity, and they may have contributed to physical adsorption mechanisms dominating the overall adsorption process (the low activation energy for all of the biochars). Modified Freundlich and intraparticle diffusion models were used to describe the kinetics of the adsorption process. Copyright © 2015 Elsevier Ltd. All rights reserved.

Application of volume-retarded osmosis and low-pressure membrane hybrid process for water reclamation.

PubMed

Im, Sung-Ju; Choi, Jungwon; Lee, Jung-Gil; Jeong, Sanghyun; Jang, Am

2018-03-01

A new concept of volume-retarded osmosis and low-pressure membrane (VRO-LPM) hybrid process was developed and evaluated for the first time in this study. Commercially available forward osmosis (FO) and ultrafiltration (UF) membranes were employed in a VRO-LPM hybrid process to overcome energy limitations of draw solution (DS) regeneration and production of permeate in the FO process. To evaluate its feasibility as a water reclamation process, and to optimize the operational conditions, cross-flow FO and dead-end mode UF processes were individually evaluated. For the FO process, a DS concentration of 0.15 g mL -1 of polysulfonate styrene (PSS) was determined to be optimal, having a high flux with a low reverse salt flux. The UF membrane with a molecular weight cut-off of 1 kDa was chosen for its high PSS rejection in the LPM process. As a single process, UF (LPM) exhibited a higher flux than FO, but this could be controlled by adjusting the effective membrane area of the FO and UF membranes in the VRO-LPM system. The VRO-LPM hybrid process only required a circulation pump for the FO process. This led to a decrease in the specific energy consumption of the VRO-LPM process for potable water production, that was similar to the single FO process. Therefore, the newly developed VRO-LPM hybrid process, with an appropriate DS selection, can be used as an energy efficient water production method, and can outperform conventional water reclamation processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Single-dose volume regulation algorithm for a gas-compensated intrathecal infusion pump.

PubMed

Nam, Kyoung Won; Kim, Kwang Gi; Sung, Mun Hyun; Choi, Seong Wook; Kim, Dae Hyun; Jo, Yung Ho

2011-01-01

The internal pressures of medication reservoirs of gas-compensated intrathecal medication infusion pumps decrease when medication is discharged, and these discharge-induced pressure drops can decrease the volume of medication discharged. To prevent these reductions, the volumes discharged must be adjusted to maintain the required dosage levels. In this study, the authors developed an automatic control algorithm for an intrathecal infusion pump developed by the Korean National Cancer Center that regulates single-dose volumes. The proposed algorithm estimates the amount of medication remaining and adjusts control parameters automatically to maintain single-dose volumes at predetermined levels. Experimental results demonstrated that the proposed algorithm can regulate mean single-dose volumes with a variation of <3% and estimate the remaining medication volume with an accuracy of >98%. © 2010, Copyright the Authors. Artificial Organs © 2010, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Graded changes in enamel component volumes resulted from a short tooth bleaching procedure.

PubMed

Ferreira, Artemisa Fernanda Moura; Perez, Flávia Maria de Moraes Ramos; Limeira Júnior, Francisco de Assis; de Moura, Mirella de Fátima Liberato; de Sousa, Frederico Barbosa

2016-05-01

To test the hypothesis that changes in enamel component volumes (mineral, organic, and water volumes, and permeability) are graded from outer to inner enamel after a short bleaching procedure. Extracted unerupted human third molars had half of their crowns bleached (single bleaching session, 3 × 15 min), and tooth shade changes in bleached parts were analyzed with a spectrophotometer. Ground sections were prepared, component volumes and permeability were quantified at histological points located at varying distances from the enamel surface (n=10 points/location), representing conditions before and after bleaching. Tooth shade changes were significant (p<0.001; 95% CI=-1/-8; power=99%), and most of the enamel layer was unaffected after bleaching, except at the outer layers. Multiple analysis of covariances revealed that most of the variance of the change in enamel composition after bleaching was explained by the combination of the set of types of component volume (in decreasing order of relevance: mineral loss, organic gain, water gain, and decrease in permeability) with the set of distances from the enamel surface (graded from the enamel surface inward) (canonical R(2)=0.97; p<0.0001; power>99%). Changes in enamel composition after a short bleaching procedure followed a gradient within component volumes (mineral loss>organic gain>water gain>decrease in permeability) and decreased from the enamel surface inward. Copyright © 2016 Elsevier Ltd. All rights reserved.

Magnetic susceptibility, artifact volume in MRI, and tensile properties of swaged Zr-Ag composites for biomedical applications.

PubMed

Imai, Haruki; Tanaka, Yoji; Nomura, Naoyuki; Doi, Hisashi; Tsutsumi, Yusuke; Ono, Takashi; Hanawa, Takao

2017-02-01

Zr-Ag composites were fabricated to decrease the magnetic susceptibility by compensating for the magnetic susceptibility of their components. The Zr-Ag composites with a different Zr-Ag ratio were swaged, and their magnetic susceptibility, artifact volume, and mechanical properties were evaluated by magnetic balance, three-dimensional (3-D) artifact rendering, and a tensile test, respectively. These properties were correlated with the volume fraction of Ag using the linear rule of mixture. We successfully obtained the swaged Zr-Ag composites up to the reduction ratio of 96% for Zr-4, 16, 36, 64Ag and 86% for Zr-81Ag. However, the volume fraction of Ag after swaging tended to be lower than that before swaging, especially for Ag-rich Zr-Ag composites. The magnetic susceptibility of the composites linearly decreased with the increasing volume fraction of Ag. No artifact could be estimated with the Ag volume fraction in the range from 93.7% to 95.4% in three conditions. Young's modulus, ultimate tensile strength (UTS), and 0.2% yield strength of Zr-Ag composites showed slightly lower values compared to the estimated values using a linear rule of mixture. The decrease in magnetic susceptibility of Zr and Ag by alloying or combining would contribute to the decrease of the Ag fraction, leading to the improvement of mechanical properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

Corpus callosal atrophy and associations with cognitive impairment in Parkinson disease

PubMed Central

Bledsoe, Ian O.; Merkitch, Doug; Dinh, Vy; Bernard, Bryan; Stebbins, Glenn T.

2017-01-01

Objective: To investigate atrophy of the corpus callosum on MRI in Parkinson disease (PD) and its relationship to cognitive impairment. Methods: One hundred patients with PD and 24 healthy control participants underwent clinical and neuropsychological evaluations and structural MRI brain scans. Participants with PD were classified as cognitively normal (PD-NC; n = 28), having mild cognitive impairment (PD-MCI; n = 47), or having dementia (PDD; n = 25) by Movement Disorder Society criteria. Cognitive domain (attention/working memory, executive function, memory, language, visuospatial function) z scores were calculated. With the use of FreeSurfer image processing, volumes for total corpus callosum and its subsections (anterior, midanterior, central, midposterior, posterior) were computed and normalized by total intracranial volume. Callosal volumes were compared between participants with PD and controls and among PD cognitive groups, covarying for age, sex, and PD duration and with multiple comparison corrections. Regression analyses were performed to evaluate relationships between callosal volumes and performance in cognitive domains. Results: Participants with PD had reduced corpus callosum volumes in midanterior and central regions compared to healthy controls. Participants with PDD demonstrated decreased callosal volumes involving multiple subsections spanning anterior to posterior compared to participants with PD-MCI and PD-NC. Regional callosal atrophy predicted cognitive domain performance such that central volumes were associated with the attention/working memory domain; midposterior volumes with executive function, language, and memory domains; and posterior volumes with memory and visuospatial domains. Conclusions: Notable volume loss occurs in the corpus callosum in PD, with specific neuroanatomic distributions in PDD and relationships of regional atrophy to different cognitive domains. Callosal volume loss may contribute to clinical manifestations of PD cognitive impairment. PMID:28235816

Production of deerbrush and mountain whitethorn related to shrub volume and overstory crown closure

Treesearch

John G. Kie

1985-01-01

Annual production by deerbrush (Ceanothus integerrimus) and mountain whitethorn shrubs (C. cordulatus) in the south-central Sierra Nevada of California was related to shrub volume, volume squared, and overstory crown closure by regression models. production increased as shrub volume and volume squared increased, and decreased as...

Studies on vibration characteristics of a pear using finite element method*

PubMed Central

Song, Hui-zhi; Wang, Jun; Li, Yong-hui

2006-01-01

The variation of the vibration characteristics of a Huanghua pear was investigated using finite element simulations. A new image processing technique was used to obtain the unsymmetrical and un-spherical geometrical model of a pear. The vibration characteristics of this type of pear with the correlation of its behavior with geometrical configurations and material characteristics were investigated using numerical modal analysis. The results showed that the eigenfrequency increased with the increasing pear Young’s modulus, while decreased with increasing pear density, and decreased with increasing pear volume. The results of this study provided foundation for further investigations of the physical characteristics of fruits and vegetables by using finite element simulations. PMID:16691644

Energy dissipation in a finite volume of magnetic fluid

NASA Astrophysics Data System (ADS)

Bashtovoi, V.; Motsar, A.; Reks, A.

2017-06-01

This study is devoted to investigation of energy dissipation processes which happen in a magnetic fluid drop with compound magnet during its motion in cylindrical non magnetic container. The possibility of energy dissipation control by means of electromagnetic field is examined. It's found that a change of magnetic field of compound magnet can lead to both increase and decrease of oscillation decay time and relative damping factor can be varied in a range of ±35%.

Stereological study of developing glomerular forms during human fetal kidney development.

PubMed

Dakovic Bjelakovic, Marija; Vlajkovic, Slobodan; Petrovic, Aleksandar; Bjelakovic, Marko; Antic, Milorad

2018-05-01

Human fetal kidney development is a complex and stepwise process. The number, shape, size and distribution of glomeruli provide important information on kidney organization. The aim of this study was to quantify glomerular developing forms during human fetal kidney development using stereological methods. Kidney tissue specimens of 40 human fetuses with gestational ages ranging from 9 to 40 weeks were analyzed. Specimens were divided into eight groups based on gestational age, each corresponding to 1 lunar month. Stereological methods were used at the light microscopy level to estimate volume, surface and numerical density of the glomerular developing forms. During gestation, nephrogenesis continually advanced, and the number of nephrons increased. Volume, surface and numerical densities of vesicular forms and S-shaped bodies decreased gradually in parallel with gradual increases in estimated stereological parameters for vascularized glomeruli. Volume density and surface density of vascularized glomeruli increased gradually during fetal kidney development, and numerical density increased until the seventh lunar month. A relative decrease in vascularized glomeruli per unit volume of cortex occurred during the last 3 lunar months. Nephrogenesis began to taper off by 32 weeks and was completed by 36 weeks of gestation. The last sample in which we observed vesicles was from a fetus aged 32 weeks, and the last sample with S-shaped bodies was from a fetus aged 36 weeks. The present study is one of few quantitative studies conducted on human kidney development. Knowledge of normal human kidney morphogenesis during development could be important for future medical practice. Events occurring during fetal life may have significant consequences later in life.

Effect of norepinephrine on swelling-induced potassium transport in duck red cells. Evidence against a volume-regulatory decrease under physiological conditions

PubMed Central

1985-01-01

Duck red cells exhibit specific volume-sensitive ion transport processes that are inhibited by furosemide, but not by ouabain. Swelling cells in a hypotonic synthetic medium activates a chloride- dependent, but sodium-independent, potassium transport. Shrinking cells in a hypertonic synthetic medium stimulates an electrically neutral co- transport of [Na + K + 2 Cl] with an associated 1:1 K/K (or K/Rb) exchange. These shrinkage-induced modes can also be activated in both hypo- and hypertonic solutions by beta-adrenergic catecholamines (e.g., norepinephrine). Freshly drawn cells spontaneously shrink approximately 4-5% when removed from the influence of endogenous plasma catecholamines, either by incubation in a catecholamine-free, plasma- like synthetic medium, or in plasma to which a beta-receptor blocking dose of propranolol has been added. This spontaneous shrinkage resembles the response of hypotonically swollen cells in that it is due to a net loss of KCl with no change in cell sodium. Norepinephrine abolishes the net potassium transport seen in both fresh and hypotonically swollen cells. Moreover, cells swollen in diluted plasma, at physiological pH and extracellular potassium, show no net loss of KCl and water ("volume-regulatory decrease") unless propranolol is added. Examination of the individual cation fluxes in the presence of catecholamines demonstrates that activation of [Na + K + 2Cl] co- transport with its associated K/Rb exchange prevents, or overrides, swelling-induced [K + Cl] co-transport. These results, therefore, cast doubt on whether the swelling-induced [K + Cl] system can serve a volume-regulatory function under in vivo conditions. PMID:3998706

Short-term physical activity intervention decreases femoral bone marrow adipose tissue in young children: a pilot study

PubMed Central

Casazza, K; Hanks, LJ; Hidalgo, B; Hu, HH; Affuso, O

2011-01-01

Mechanical stimulation is necessary for maximization of geometrical properties of bone mineralization contributing to long-term strength. The amount of mineralization in bones has been reciprocally related to volume of bone marrow adipose tissue and this relationship is suggested to be an independent predictor of fracture. Physical activity represents an extrinsic factor that impacts both mineralization and marrow volume exerting permissive capacity of the growing skeleton to achieve its full genetic potential. Because geometry- and shape-determining processes primarily manifest during the linear growth period, the accelerated structural changes accompanying early childhood (ages 3 to 6 y) may have profound impact on lifelong bone health. The objective of this pilot study was to determine if a short-term physical activity intervention in young children would result in augmentation of geometric properties of bone. Three days per week the intervention group (n=10) participated in 30 minutes of moderate intensity physical activity, such as jumping, hopping and running, and stretching activities, whereas controls (n=10) underwent usual activities during the 10-week intervention period. Femoral bone marrow adipose tissue volume and total body composition were assessed by magnetic resonance imaging and dual-energy X-ray absorptiometry, respectively, at baseline and after ten weeks. Although after 10-weeks, intergroup differences were not observed, a significant decrease in femoral marrow adipose tissue volume was observed in those participating in physical activity intervention. Our findings suggest physical activity may improve bone quality via antagonistic effects on femoral bone marrow adipose tissue and possibly long-term agonistic effects on bone mineralization. PMID:21939791

Decreased pyramidal neuron size in Brodmann areas 44 and 45 in patients with autism.

PubMed

Jacot-Descombes, Sarah; Uppal, Neha; Wicinski, Bridget; Santos, Micaela; Schmeidler, James; Giannakopoulos, Panteleimon; Heinsen, Helmut; Heinsein, Helmut; Schmitz, Christoph; Hof, Patrick R

2012-07-01

Autism is a neurodevelopmental disorder characterized by deficits in social interaction and social communication, as well as by the presence of repetitive and stereotyped behaviors and interests. Brodmann areas 44 and 45 in the inferior frontal cortex, which are involved in language processing, imitation function, and sociality processing networks, have been implicated in this complex disorder. Using a stereologic approach, this study aims to explore the presence of neuropathological differences in areas 44 and 45 in patients with autism compared to age- and hemisphere-matched controls. Based on previous evidence in the fusiform gyrus, we expected to find a decrease in the number and size of pyramidal neurons as well as an increase in volume of layers III, V, and VI in patients with autism. We observed significantly smaller pyramidal neurons in patients with autism compared to controls, although there was no difference in pyramidal neuron numbers or layer volumes. The reduced pyramidal neuron size suggests that a certain degree of dysfunction of areas 44 and 45 plays a role in the pathology of autism. Our results also support previous studies that have shown specific cellular neuropathology in autism with regionally specific reduction in neuron size, and provide further evidence for the possible involvement of the mirror neuron system, as well as impairment of neuronal networks relevant to communication and social behaviors, in this disorder.

Effects of oxidation reduction potential in the bypass micro-aerobic sludge zone on sludge reduction for a modified oxic-settling-anaerobic process.

PubMed

Li, Kexun; Wang, Yi; Zhang, Zhongpin; Liu, Dongfang

2014-01-01

Batch experiments were conducted to determine the effect of oxidation reduction potential (ORP) on sludge reduction in a bypass micro-aerobic sludge reduction system. The system was composed of a modified oxic-settling-anaerobic process with a sludge holding tank in the sludge recycle loop. The ORPs in the micro-aerobic tanks were set at approximately +350, -90, -150, -200 and -250 mV, by varying the length of aeration time for the tanks. The results show that lower ORP result in greater sludge volume reduction, and the sludge production was reduced by 60% at the lowest ORP. In addition, low ORP caused extracellular polymer substances dissociation and slightly reduced sludge activity. Comparing the sludge backflow characteristics of the micro-aerobic tank's ORP controlled at -250 mV with that of +350 mV, the average soluble chemical oxygen (SCOD), TN and TP increased by 7, 0.4 and 2 times, median particle diameter decreased by 8.5 μm and the specific oxygen uptake rate (SOUR) decreased by 0.0043 milligram O2 per gram suspended solids per minute. For the effluent, SCOD and TN and TP fluctuated around 30, 8.7 and 0.66 mg/L, respectively. Therefore, the effective assignment of ORP in the micro-aerobic tank can remarkably reduce sludge volume and does not affect final effluent quality.

Cerebral blood flow velocity and cranial fluid volume decrease during +Gz acceleration

NASA Technical Reports Server (NTRS)

Kawai, Y.; Puma, S. C.; Hargens, A. R.; Murthy, G.; Warkander, D.; Lundgren, C. E.

1997-01-01

Cerebral blood flow (CBF) velocity and cranial fluid volume, which is defined as the total volume of intra- and extracranial fluid, were measured using transcranial Doppler ultrasonography and rheoencephalography, respectively, in humans during graded increase of +Gz acceleration (onset rate: 0.1 G/s) without straining maneuvers. Gz acceleration was terminated when subjects' vision decreased to an angle of less than or equal to 60 degrees, which was defined as the physiological end point. In five subjects, mean CBF velocity decreased 48% from a baseline value of 59.4 +/- 11.2 cm/s to 31.0 +/- 5.6 cm/s (p<0.01) with initial loss of peripheral vision at 5.7 +/- 0.9 Gz. On the other hand, systolic CBF velocity did not change significantly during increasing +Gz acceleration. Cranial impedance, which is proportional to loss of cranial fluid volume, increased by 2.0 +/- 0.8% above the baseline value at the physiological end point (p<0.05). Both the decrease of CBF velocity and the increase of cranial impedance correlated significantly with Gz. These results suggest that +Gz acceleration without straining maneuvers decreases CBF velocity to half normal and probably causes a caudal fluid shift from both intra- and extracranial tissues.

Deterioration of left ventricular chamber performance after bed rest : "cardiovascular deconditioning" or hypovolemia?

NASA Technical Reports Server (NTRS)

Perhonen, M. A.; Zuckerman, J. H.; Levine, B. D.; Blomqvist, C. G. (Principal Investigator)

2001-01-01

BACKGROUND: Orthostatic intolerance after bed rest is characterized by hypovolemia and an excessive reduction in stroke volume (SV) in the upright position. We studied whether the reduction in SV is due to a specific adaptation of the heart to head-down tilt bed rest (HDTBR) or acute hypovolemia alone. METHODS AND RESULTS: We constructed left ventricular (LV) pressure-volume curves from pulmonary capillary wedge pressure and LV end-diastolic volume and Starling curves from pulmonary capillary wedge pressure and SV during lower body negative pressure and saline loading in 7 men (25+/-2 years) before and after 2 weeks of -6 degrees HDTBR and after the acute administration of intravenous furosemide. Both HDTBR and hypovolemia led to a similar reduction in plasma volume. However, baseline LV end-diastolic volume decreased by 20+/-4% after HDTBR and by 7+/-2% after hypovolemia (interaction P<0.001). Moreover, SV was reduced more and the Starling curve was steeper during orthostatic stress after HDTBR than after hypovolemia. The pressure-volume curve showed a leftward shift and the equilibrium volume of the left ventricle was decreased after HDTBR; however, after hypovolemia alone, the curve was identical, with no change in equilibrium volume. Lower body negative pressure tolerance was reduced after both conditions; it decreased by 27+/-7% (P<0.05) after HDTBR and by 18+/-8% (P<0.05) after hypovolemia. CONCLUSIONS: Chronic HDTBR leads to ventricular remodeling, which is not seen with equivalent degrees of acute hypovolemia. This remodeling leads to a greater decrease in SV during orthostatic stress after bed rest than hypovolemia alone, potentially contributing to orthostatic intolerance.

Tubular system volume changes in twitch fibres from toad and rat skeletal muscle assessed by confocal microscopy

PubMed Central

Launikonis, Bradley S; Stephenson, D George

2002-01-01

The volume of the extracellular compartment (tubular system) within intact muscle fibres from cane toad and rat was measured under various conditions using confocal microscopy. Under physiological conditions at rest, the fractional volume of the tubular system (t-sysVol) was 1.38 ± 0.09 % (n = 17), 1.41 ± 0.09 % (n = 12) and 0.83 ± 0.07 % (n = 12) of the total fibre volume in the twitch fibres from toad iliofibularis muscle, rat extensor digitorum longus muscle and rat soleus muscle, respectively. In toad muscle fibres, the t-sysVol decreased by 30 % when the tubular system was fully depolarized and decreased by 15 % when membrane cholesterol was depleted from the tubular system with methyl-β-cyclodextrin but did not change as the sarcomere length was changed from 1.93 to 3.30 μm. There was also an increase by 30 % and a decrease by 25 % in t-sysVol when toad fibres were equilibrated in solutions that were 2.5-fold hypertonic and 50 % hypotonic, respectively. When the changes in total fibre volume were taken into consideration, the t-sysVol expressed as a percentage of the isotonic fibre volume did actually decrease as tonicity increased, revealing that the tubular system in intact fibres cannot be compressed below 0.9 % of the isotonic fibre volume. The results can be explained in terms of forces acting at the level of the tubular wall. These observations have important physiological implications showing that the tubular system is a dynamic membrane structure capable of changing its volume in response to the membrane potential, cholesterol depletion and osmotic stress but not when the sarcomere length is changed in resting muscle. PMID:11790823

Utility of Early Post-operative High Resolution Volumetric MR Imaging after Transsphenoidal Pituitary Tumor Surgery

PubMed Central

Patel, Kunal S.; Kazam, Jacob; Tsiouris, Apostolos J.; Anand, Vijay K.; Schwartz, Theodore H.

2014-01-01

Objective Controversy exists over the utility of early post-operative magnetic resonance imaging (MRI) after transsphenoidal pituitary surgery for macroadenomas. We investigate whether valuable information can be derived from current higher resolution scans. Methods Volumetric MRI scans were obtained in the early (<10 days) and late (>30 days) post-operative periods in a series of patients undergoing transsphenoidal pituitary surgery. The volume of the residual tumor, resection cavity, and corresponding visual field tests were recorded at each time point. Statistical analyses of changes in tumor volume and cavity size were calculated using the late MRI as the gold standard. Results 40 patients met the inclusion criteria. Pre-operative tumor volume averaged 8.8 cm3. Early postoperative assessment of average residual tumor volume (1.18 cm3) was quite accurate and did not differ statistically from late post-operative volume (1.23 cm3, p=.64), indicating the utility of early scans to measure residual tumor. Early scans were 100% sensitive and 91% specific for predicting ≥ 98% resection (p<.001, Fisher’s exact test). The average percent decrease in cavity volume from pre-operative MRI (tumor volume) to early post-operative imaging was 45% with decreases in all but 3 patients. There was no correlation between the size of the early cavity and the visual outcome. Conclusions Early high resolution volumetric MRI is valuable in determining the presence or absence of residual tumor. Cavity volume almost always decreases after surgery and a lack of decrease should alert the surgeon to possible persistent compression of the optic apparatus that may warrant re-operation. PMID:25045791

Relationship Between Lymph Node Volume and Pain Following Certolizumab Therapy for Rheumatoid Arthritis Flare: A Pilot Study.

PubMed

Rahimi, Homaira; Dieudonne, Gregory; Kheyfits, Valeriy; Bouta, Echoe M; Wood, Ronald W; Barrett, Rick; Moorehead, Sharon; Schwarz, Edward M; Ritchlin, Christopher T

2016-01-01

The mechanisms that trigger flare in rheumatoid arthritis (RA) are unknown. In murine arthritis models, dysfunctional lymph node (LN) drainage is associated with joint flare. To examine if LN alterations are associated with RA flare, we analyzed the change in LN volume via contrast-enhanced magnetic resonance imaging (CE-MRI) in patients with active joint flare at baseline and 16 weeks after certolizumab pegol (CZP) therapy. We also assessed the changes in popliteal or epitrochlear LN volumes versus the Rheumatoid and Arthritis Outcome Score (RAOS) (knee), or the Michigan Hand Questionnaire (MHQ; wrist/hand), and Disease Activity Score 28 (DAS28), at baseline and 16 weeks. Total LN volume in 7 of 10 patients with measurable LN on CE-MRI significantly decreased 16 weeks after CZP therapy (mean decrease 37%; P = 0.0019). Improvement in knee pain measured by the RAOS ( P = 0.03) inversely correlated with a decrease in total popliteal LN volume ( R 2 = 0.94). All patients demonstrated significant improvement in DAS28 (mean decrease 1.48; P = 0.0002). For flare in the hand, significant improvement in activities of daily living (ADL) as measured by the MHQ was observed (left hand mean improvement 20%; P = 0.02; right hand mean improvement 37%; P = 0.03). RA patients with the smallest change in LN volume during anti-tumor necrosis factor (anti-TNF) therapy experienced the greatest pain relief in symptomatic knee joints. Moreover, the remarkably linear inverse correlation between LN volume and joint pain observed in this small clinical pilot provides initial evidence to support the concept that dynamic changes in draining LN volume are a biomarker of clinical response to therapy in RA.

Characterization of dynamics in complex lyophilized formulations: II. Analysis of density variations in terms of glass dynamics and comparisons with global mobility, fast dynamics, and Positron Annihilation Lifetime Spectroscopy (PALS)

PubMed Central

Chieng, Norman; Cicerone, Marcus T.; Zhong, Qin; Liu, Ming; Pikal, Michael J.

2013-01-01

Amorphous HES/disaccharide (trehalose or sucrose) formulations, with and without added polyols (glycerol and sorbitol) and disaccharide formulations of human growth hormone (hGH), were prepared by freeze drying and characterized with particular interest in methodology for using high precision density measurements to evaluate free volume changes and a focus on comparisons between “free volume” changes obtained from analysis of density data, fast dynamics (local mobility), and PALS characterization of “free volume” hole size. Density measurements were performed using a helium gas pycnometer, and fast dynamics was characterized using incoherent neutron scattering spectrometer. Addition of sucrose and trehalose to hGH decreases free volume in the system with sucrose marginally more effective than trehalose, consistent with superior pharmaceutical stability of sucrose hGH formulations well below Tg relative to trehalose. We find that density data may be analyzed in terms of free volume changes by evaluation of volume changes on mixing and calculation of apparent specific volumes from the densities. Addition of sucrose to HES decreases free volume, but the effect of trehalose is not detectable above experimental error. Addition of sorbitol or glycerol to HES/trehalose base formulations appears to significantly decrease free volume, consistent with the positive impact of such additions on pharmaceutical stability (i.e., degradation) in the glassy state. Free volume changes, evaluated from density data, fast dynamics amplitude of local motion, and PALS hole size data generally are in qualitative agreement for the HES/disaccharide systems studied. All predict decreasing molecular mobility as disaccharides are added to HES. Global mobility as measured by enthalpy relaxation times, increases as disaccharides, particularly sucrose, are added to HES. PMID:23623797

Impairment of left ventricular function during coronary angioplastic occlusion evaluated with a nonimaging scintillation probe.

PubMed

Hartmann, A; Maul, F D; Zimny, M; Klepzig, H; Vallbracht, C; Kneissl, H G; Schräder, R; Hör, G; Kaltenbach, M

1991-09-01

Impairment of left ventricular function during controlled myocardial ischemia induced by coronary angioplasty has been reported from angiographic and echocardiographic studies. Ejection fraction, peak ejection, peak filling rates, and end-systolic and end-diastolic volumes were investigated before, during and after coronary occlusion on-line with a nonimaging scintillation probe. The study consisted of 18 patients (mean age 59 +/- 10 years) with coronary artery stenosis of greater than 70%. During balloon inflation of 60 seconds' duration, coronary occlusion pressure was 31.6 +/- 12 mm Hg. There was no significant change in heart rate. Delay between first and second dilatation was 109 +/- 63 seconds. Ejection fraction decreased from 53 +/- 16 to 40 +/- 12% (first dilatation, p less than 0.01) and to 39 +/- 14% (second dilatation, p less than 0.01) and recovered to 51 +/- 16% 5 minutes after the second dilatation. Peak ejection rate was significantly reduced during the first and second balloon inflations. Peak filling rate decreased from 2.5 +/- 0.8 to 2.0 +/- 0.7 end-diastolic volume.s-1 (first dilatation, p less than 0.01) and to 1.8 +/- 0.7 end-diastolic volume.s-1 (second dilatation, p less than 0.01) and remained reduced at 2.2 +/- 0.7 end-diastolic volume.s-1 (p = not significant) at 5 minutes after the second dilatation. End-systolic and end-diastolic volumes increased significantly during the first and second dilatations and returned to normal after dilatation. It is concluded that short, controlled myocardial ischemia during coronary angioplasty leads to a decrease in systolic and diastolic left ventricular function. Sequential dilatations do not further decrease function if a sufficient interval is kept.

Morphometric analysis of abdominal organs and rib cage: Implication for risk of solid organ injuries in children.

PubMed

Harbaugh, Calista M; Shlykov, Maksim A; Tsuchida, Ryan E; Holcombe, Sven A; Hirschl, Jake; Wang, Stewart C; Ehrlich, Peter F

2015-06-01

Motor vehicle crashes are the leading cause of injury-related mortality in children, with a higher rate of multiorgan injuries than in adults. This may be related to increased solid organ volume relative to abdominal cavity and decreased protection of an underdeveloped cartilaginous rib cage in young children. To date, these anatomic relationships have not been fully described. Our study used analytic morphomics to obtain precise measures of the pediatric liver, spleen, kidneys, and ribs. This pilot study included 215 trauma patients (aged 0-18 years) with anonymized computed tomography (CT) scans. Liver, spleen, and kidney volumes were modeled using semiautomatic algorithms (MATLAB 2013a, MathWorks Inc., Natick, MA). Thirty-one scans were adequate to model the rib cage. Pearson's r was used to correlate absolute organ volume, fractional organ volume, and organ exposure with age and weight. Spleen, right and left kidney, and liver volumes increased with age and weight (p < 0.01). Right/left kidney and liver fractional volumes decreased with age (p < 0.01), whereas spleen fractional volume remained relatively constant. Exposed surface area of the liver only significantly decreased with age in the anterior (p < 0.01), right (p < 0.01), and posterior views (p = 0.02). With this study, we have demonstrated the ability to model solid organ and rib cage anatomy of children using cross-sectional imaging. In younger children, there may be a decrease in fractional organ volume and increase in liver surface exposure, although analysis of a larger sample size is warranted. In the future, this information may be used to improve the design of safety restraints in motor vehicles.

Novel analysis of 4DCT imaging quantifies progressive increases in anatomic dead space during mechanical ventilation in mice.

PubMed

Kim, Elizabeth H; Preissner, Melissa; Carnibella, Richard P; Samarage, Chaminda R; Bennett, Ellen; Diniz, Marcio A; Fouras, Andreas; Zosky, Graeme R; Jones, Heather D

2017-09-01

Increased dead space is an important prognostic marker in early acute respiratory distress syndrome (ARDS) that correlates with mortality. The cause of increased dead space in ARDS has largely been attributed to increased alveolar dead space due to ventilation/perfusion mismatching and shunt. We sought to determine whether anatomic dead space also increases in response to mechanical ventilation. Mice received intratracheal lipopolysaccharide (LPS) or saline and mechanical ventilation (MV). Four-dimensional computed tomography (4DCT) scans were performed at onset of MV and after 5 h of MV. Detailed measurements of airway volumes and lung tidal volumes were performed using image analysis software. The forced oscillation technique was used to obtain measures of airway resistance, tissue damping, and tissue elastance. The ratio of airway volumes to total tidal volume increased significantly in response to 5 h of mechanical ventilation, regardless of LPS exposure, and airways demonstrated significant variation in volumes over the respiratory cycle. These findings were associated with an increase in tissue elastance (decreased lung compliance) but without changes in tidal volumes. Airway volumes increased over time with exposure to mechanical ventilation without a concomitant increase in tidal volumes. These findings suggest that anatomic dead space fraction increases progressively with exposure to positive pressure ventilation and may represent a pathological process. NEW & NOTEWORTHY We demonstrate that anatomic dead space ventilation increases significantly over time in mice in response to mechanical ventilation. The novel functional lung-imaging techniques applied here yield sensitive measures of airway volumes that may have wide applications. Copyright © 2017 the American Physiological Society.

The Effects of Hydrotherapy on Anxiety, Pain, Neuroendocrine Responses, and Contraction Dynamics During Labor

PubMed Central

Benfield, Rebecca D.; Hortobágyi, Tibor; Tanner, Charles J.; Swanson, Melvin; Heitkemper, Margaret M.; Newton, Edward R.

2013-01-01

Background Hydrotherapy (immersion, or bathing) is used worldwide to promote relaxation and decrease parturient anxiety and pain in labor, but the psychophysiological effects of this intervention remain obscure. Design A pre-test post-test design with repeated measures was used to examine the effects of hydrotherapy on maternal anxiety and pain, neuroendocrine responses, plasma volume shift and uterine contractions during labor. Correlations among variables were examined at three time points (pre-immersion and twice during hydrotherapy). Methods Eleven term women (mean age 24.5 years) in spontaneous labor were immersed to the xiphoid in 37°C water for 1 hr. Blood samples and measures of anxiety and pain were obtained under dry baseline conditions and repeated at 15 and 45 min of hydrotherapy. Uterine contractions were monitored telemetrically. Results Hydrotherapy was associated with decreases in anxiety, vasopressin and oxytocin levels at 15 and 45 min (all p < .05). There were no significant differences between pre-immersion and immersion pain or cortisol levels. Pain decreased more for women with high baseline pain than for women with low baseline levels at 15 and 45 min. Cortisol levels decreased twice as much at 15 min of hydrotherapy for women with high baseline pain as for those with low baseline pain. Beta-endorphin levels increased at 15 min but did not differ between baseline and 45 min. During immersion, uterine-contraction frequency decreased. A positive plasma volume shift at 15 min was correlated with contraction duration. Conclusions Hydrotherapy during labor affects neuroendocrine responses that modify psychophysiological processes. PMID:20453024

Pharmacodynamic effects of pilocarpine eye drop enhanced by decreasing its volume of instillation.

PubMed

Lal, A; Kataria, V; Rajpal, A; Khanna, N

1995-07-01

Previous studies have proved that as the volume of the drug solution instilled into the eye is decreased, the fraction of the dose absorbed into the ocular tissue is increased and the adverse drug reactions lowered. The present study investigated the acute effects of different drop volumes (10 microliters, 20 microliters, 40 microliters, and 80 microliters) of pilocarpine nitrate (2%) on pupil diameter, heart rate, and adverse reaction profile, in 12 healthy human volunteers. The drop volumes of 10 microliters and 20 microliters produced more miosis and less side effects than 40 microliters and 80 microliters drop volumes. This may be due to more penetration of the drug into the ocular tissue and less drainage into the nasolacrimal system.

Flow and volume dependence of rat airway resistance during constant flow inflation and deflation.

PubMed

Rubini, Alessandro; Carniel, Emanuele Luigi; Parmagnani, Andrea; Natali, Arturo Nicola

2011-12-01

The aim of this study was to measure the flow and volume dependence of both the ohmic and the viscoelastic pressure dissipations of the normal rat respiratory system separately during inflation and deflation. The study was conducted in the Respiratory Physiology Laboratory in our institution. Measurements were obtained for Seven albino Wistar rats of both sexes by using the flow interruption method during constant flow inflations and deflations. Measurements included anesthesia induction, tracheostomy and positioning of a tracheal cannula, positive pressure ventilation, constant flow respiratory system inflations and deflations at two different volumes and flows. The ohmic resistance exhibited volume and flow dependence, decreasing with lung volume and increasing with flow rate, during both inflation and deflation. The stress relaxation-related viscoelastic resistance also exhibited volume and flow dependence. It decreased with the flow rate at a constant lung volume during both inflation and deflation, but exhibited a different behavior with the lung volume at a constant flow rate (i.e., increased during inflations and decreased during deflations). Thus, stress relaxation in the rat lungs exhibited a hysteretic behavior. The observed flow and volume dependence of respiratory system resistance may be predicted by an equation derived from a model of the respiratory system that consists of two distinct compartments. The equation agrees well with the experimental data and indicates that the loading time is the critical parameter on which stress relaxation depends, during both lung inflation and deflation.

Differential regional gray matter volumes in patients with on-line game addiction and professional gamers

PubMed Central

Han, Doug Hyun; Lyoo, In Kyoon; Renshaw, Perry F.

2015-01-01

Patients with on-line game addiction (POGA) and professional video game players play video games for extended periods of time, but experience very different consequences for their on-line game play. Brain regions consisting of anterior cingulate, thalamus and occpito-temporal areas may increase the likelihood of becoming a pro-gamer or POGA. Twenty POGA, seventeen pro-gamers, and eighteen healthy comparison subjects (HC) were recruited. All magnetic resonance imaging (MRI) was performed on a 1.5 Tesla Espree MRI scanner (SIEMENS, Erlangen, Germany). Voxel-wise comparisons of gray matter volume were performed between the groups using the two-sample t-test with statistical parametric mapping (SPM5). Compared to HC, the POGA group showed increased impulsiveness and perseverative errors, and volume in left thalamus gray matter, but decreased gray matter volume in both inferior temporal gyri, right middle occipital gyrus, and left inferior occipital gyrus, compared with HC. Pro-gamers showed increased gray matter volume in left cingulate gyrus, but decreased gray matter volume in left middle occipital gyrus and right inferior temporal gyrus compared with HC. Additionally, the pro-gamer group showed increased gray matter volume in left cingulate gyrus and decreased left thalamus gray matter volume compared with the POGA group. The current study suggests that increased gray matter volumes of the left cingulate gyrus in pro-gamers and of the left thalamus in POGA may contribute to the different clinical characteristics of pro-gamers and POGA. PMID:22277302

Carbon dioxide sequestration in municipal solid waste incinerator (MSWI) bottom ash.

PubMed

Rendek, Eva; Ducom, Gaëlle; Germain, Patrick

2006-01-16

During bottom ash weathering, carbonation under atmospheric conditions induces physico-chemical evolutions leading to the pacification of the material. Fresh bottom ash samples were subjected to an accelerated carbonation using pure CO2. The aim of this work was to quantify the volume of CO2 that could be sequestrated with a view to reduce greenhouse gas emissions and investigate the possibility of upgrading some specific properties of the material with accelerated carbonation. Carbonation was performed by putting 4mm-sieved samples in a CO2 chamber. The CO2 pressure and the humidity of the samples were varied to optimize the reaction parameters. Unsieved material was also tested. Calcite formation resulting from accelerated carbonation was investigated by thermogravimetry and differential scanning calorimetry (TG/DSC) and metal leaching tests were performed. The volume of sequestrated CO2 was on average 12.5L/kg dry matter (DM) for unsieved material and 24 L/kg DM for 4mm-sieved samples. An ash humidity of 15% appeared to give the best results. The reaction was drastically accelerated at high pressure but it did not increase the volume of sequestrated CO2. Accelerated carbonation, like the natural phenomenon, reduces the dangerous nature of the material. It decreases the pH from 11.8 to 8.2 and causes Pb, Cr and Cd leaching to decrease. This process could reduce incinerator CO2 emissions by 0.5-1%.

Anatomical substrates of cognitive and clinical dimensions in first episode schizophrenia.

PubMed

Rigucci, S; Rossi-Espagnet, C; Ferracuti, S; De Carolis, A; Corigliano, V; Carducci, F; Mancinelli, I; Cicone, F; Tatarelli, R; Bozzao, A; Girardi, P; Comparelli, A

2013-10-01

To explore gray (GM) and white matter (WM) abnormalities and the relationships with neuropsychopathology in first-episode schizophrenia (FES). Nineteen patients with first episode of non-affective psychosis and 18 controls underwent a magnetic resonance voxel-based morphometry. Additionally, WM fractional anisotropy (FA) was calculated. For correlative analysis, symptoms and neuropsychological performances were scored by PANSS and by a comprehensive neuropsychological assessment respectively. Patients showed significantly decreased volume of left temporal lobe and disarray of all major WM tracts. Disorganized PANSS factor was inversely related to left cerebellar GM volume (corrected P = 0.03) and to WM FA of the left cerebellum, inferior fronto-occipital fasciculi (IFOF), and inferior longitudinal fasciculi (corrected P < 0.05). PANSS negative factor was inversely related to FA in the IFOF and superior longitudinal fasciculi (corrected P < 0.05). Impairment in facial emotion identification showed associations with temporo-occipital GM volume decrease (corrected P = 0.003) and WM disarray of superior and middle temporal gyri, anterior thalamic radiation, and superior longitudinal fasciculi (corrected P < 0.05). Speed of processing and visual memory correlated with WM abnormalities in fronto-temporal tracts. These results confirm how the structural development of key brain regions is related to neuropsychopathological dysfunction in FES, consistently with a neurodevelopmentally derived misconnection syndrome. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Computational study of textured ferroelectric polycrystals: Dielectric and piezoelectric properties of template-matrix composites

NASA Astrophysics Data System (ADS)

Zhou, Jie E.; Yan, Yongke; Priya, Shashank; Wang, Yu U.

2017-01-01

Quantitative relationships between processing, microstructure, and properties in textured ferroelectric polycrystals and the underlying responsible mechanisms are investigated by phase field modeling and computer simulation. This study focuses on three important aspects of textured ferroelectric ceramics: (i) grain microstructure evolution during templated grain growth processing, (ii) crystallographic texture development as a function of volume fraction and seed size of the templates, and (iii) dielectric and piezoelectric properties of the obtained template-matrix composites of textured polycrystals. Findings on the third aspect are presented here, while an accompanying paper of this work reports findings on the first two aspects. In this paper, the competing effects of crystallographic texture and template seed volume fraction on the dielectric and piezoelectric properties of ferroelectric polycrystals are investigated. The phase field model of ferroelectric composites consisting of template seeds embedded in matrix grains is developed to simulate domain evolution, polarization-electric field (P-E), and strain-electric field (ɛ-E) hysteresis loops. The coercive field, remnant polarization, dielectric permittivity, piezoelectric coefficient, and dissipation factor are studied as a function of grain texture and template seed volume fraction. It is found that, while crystallographic texture significantly improves the polycrystal properties towards those of single crystals, a higher volume fraction of template seeds tends to decrease the electromechanical properties, thus canceling the advantage of ferroelectric polycrystals textured by templated grain growth processing. This competing detrimental effect is shown to arise from the composite effect, where the template phase possesses material properties inferior to the matrix phase, causing mechanical clamping and charge accumulation at inter-phase interfaces between matrix and template inclusions. The computational results are compared with complementary experiments, where good agreement is obtained.

Substance P–saporin lesion of neurons with NK1 receptors in one chemoreceptor site in rats decreases ventilation and chemosensitivity

PubMed Central

Nattie, Eugene E; Li, Aihua

2002-01-01

All medullary central chemoreceptor sites contain neurokinin-1 receptor immunoreactivity (NK1R-ir). We ask if NK1R-ir neurons and processes are involved in chemoreception. At one site, the retrotrapezoid nucleus/parapyramidal region (RTN/Ppy), we injected a substance P–saporin conjugate (SP-SAP; 0.1 pmol in 100 nl) to kill NK1R-ir neurons specifically, or SAP alone as a control. We made measurements for 15 days after the injections in two groups of rats. In group 1, with unilateral injections made in the awake state via a pre-implanted guide cannula, we compared responses within rats using initial baseline data. In group 2, with bilateral injections made under anaesthesia at surgery, we compared responses between SP-SAP- and SAP-treated rats. SP-SAP treatment reduced the volume of the RTN/Ppy region that contained NK1R-ir neuronal somata and processes by 44 % (group 1) and by 47 and 40 % on each side, respectively (group 2). Ventilation () and tidal volume (VT) were decreased during air breathing in sleep and wakefulness (group 2; P < 0.001; two-way ANOVA) and Pa,CO2 was increased (group 2; P < 0.05; Student's t test). When rats breathed an air mixture containing 7 % CO2 during sleep and wakefulness, and VT were lower (groups 1 and 2; P < 0.001; ANOVA) and the Δ in air containing 7 % CO2 compared to air was decreased by 28-30 % (group 1) and 17-22 % (group 2). SP-SAP-treated rats also slept less during air breathing. We conclude that neurons with NK1R-ir somata or processes in the RTN/Ppy region are either chemosensitive or they modulate chemosensitivity. They also provide a tonic drive to breathe and may affect arousal. PMID:12381830

Substance P-saporin lesion of neurons with NK1 receptors in one chemoreceptor site in rats decreases ventilation and chemosensitivity.

PubMed

Nattie, Eugene E; Li, Aihua

2002-10-15

All medullary central chemoreceptor sites contain neurokinin-1 receptor immunoreactivity (NK1R-ir). We ask if NK1R-ir neurons and processes are involved in chemoreception. At one site, the retrotrapezoid nucleus/parapyramidal region (RTN/Ppy), we injected a substance P-saporin conjugate (SP-SAP; 0.1 pmol in 100 nl) to kill NK1R-ir neurons specifically, or SAP alone as a control. We made measurements for 15 days after the injections in two groups of rats. In group 1, with unilateral injections made in the awake state via a pre-implanted guide cannula, we compared responses within rats using initial baseline data. In group 2, with bilateral injections made under anaesthesia at surgery, we compared responses between SP-SAP- and SAP-treated rats. SP-SAP treatment reduced the volume of the RTN/Ppy region that contained NK1R-ir neuronal somata and processes by 44 % (group 1) and by 47 and 40 % on each side, respectively (group 2). Ventilation (.V(E)) and tidal volume (V(T)) were decreased during air breathing in sleep and wakefulness (group 2; P < 0.001; two-way ANOVA) and P(a,CO2) was increased (group 2; P < 0.05; Student's t test). When rats breathed an air mixture containing 7 % CO(2) during sleep and wakefulness, .V(E) and V(T) were lower (groups 1 and 2; P < 0.001; ANOVA) and the Delta.V(E) in air containing 7 % CO(2) compared to air was decreased by 28-30 % (group 1) and 17-22 % (group 2). SP-SAP-treated rats also slept less during air breathing. We conclude that neurons with NK1R-ir somata or processes in the RTN/Ppy region are either chemosensitive or they modulate chemosensitivity. They also provide a tonic drive to breathe and may affect arousal.

Quantitative CT characterization of pediatric lung development using routine clinical imaging

PubMed Central

Stein, Jill M.; Walkup, Laura L.; Brody, Alan S.; Fleck, Robert J.

2016-01-01

Background The use of quantitative CT analysis in children is limited by lack of normal values of lung parenchymal attenuation. These characteristics are important because normal lung development yields significant parenchymal attenuation changes as children age. Objective To perform quantitative characterization of normal pediatric lung parenchymal X-ray CT attenuation under routine clinical conditions in order to establish a baseline comparison to that seen in pathological lung conditions. Materials and methods We conducted a retrospective query of normal CT chest examinations in children ages 0–7 years from 2004 to 2014 using standard clinical protocol. During these examinations semi-automated lung parenchymal segmentation was performed to measure lung volume and mean lung attenuation. Results We analyzed 42 CT examinations in 39 children, ages 3 days to 83 months (mean ± standard deviation [SD] = 42±27 months). Lung volume ranged 0.10–1.72 liters (L). Mean lung attenuation was much higher in children younger than 12 months, with values as high as −380 Hounsfield units (HU) in neonates (lung volume 0.10 L). Lung volume decreased to approximately −650 HU by age 2 years (lung volume 0.47 L), with subsequently slower exponential decrease toward a relatively constant value of −860 HU as age and lung volume increased. Conclusion Normal lung parenchymal X-ray CT attenuation decreases with increasing lung volume and age; lung attenuation decreases rapidly in the first 2 years of age and more slowly thereafter. This change in normal lung attenuation should be taken into account as quantitative CT methods are translated to pediatric pulmonary imaging. PMID:27576458

Electromagnetic transponders indicate prostate size increase followed by decrease during the course of external beam radiation therapy.

PubMed

King, Benjamin L; Butler, Wayne M; Merrick, Gregory S; Kurko, Brian S; Reed, Joshua L; Murray, Brian C; Wallner, Kent E

2011-04-01

Real-time image guidance enables more accurate radiation therapy by tracking target movement. This study used transponder positions to monitor changes in prostate volume that may be a source of dosimetric and target inaccuracy. Twenty-four men with biopsy-proven T1c-T3a prostate cancer each had three electromagnetic transponders implanted transperineally. Their coordinates were recorded by the Calypso system, and the perimeter of the triangle formed by the transponders was used to calculate prostate volumes at sequential time points throughout the course of radiation therapy to a dose of 81 Gy in 1.8-Gy fractions. There was a significant decrease in mean prostate volume of 10.9% from the first to the final day of radiation therapy. The volume loss did not occur monotonically but increased in most patients (75%) during the first several weeks to a median maximum on Day 7. The volume increased by a mean of 6.1% before decreasing by a mean maximum difference of 18.4% to nadir (p < 0.001 for both increase and decrease). Glandular shrinkage was asymmetric, with the apex to right base dimension varying more than twice that of the lateral dimension. For all dimensions, the mean change was <0.5 cm. Real-time transponder positions indicated a volume increase during the initial days of radiation therapy and then significant and asymmetric shrinkage by the final day. Understanding and tracking volume fluctuations of the prostate during radiation therapy can help real-time imaging technology perform to its fullest potential. Copyright © 2011 Elsevier Inc. All rights reserved.

Impregnation of Composite Materials: a Numerical Study

NASA Astrophysics Data System (ADS)

Baché, Elliott; Dupleix-Couderc, Chloé; Arquis, Eric; Berdoyes, Isabelle

2017-12-01

Oxide ceramic matrix composites are currently being developed for aerospace applications such as the exhaust, where the parts are subject to moderately high temperatures (≈ 700 ∘C) and oxidation. These composite materials are normally formed by, among other steps, impregnating a ceramic fabric with a slurry of ceramic particles. This impregnation process can be complex, with voids possibly forming in the fabric depending on the process parameters and material properties. Unwanted voids or macroporosity within the fabric can decrease the mechanical properties of the parts. In order to design an efficient manufacturing process able to impregnate the fabric well, numerical simulations may be used to design the process as well as the slurry. In this context, a tool is created for modeling different processes. Thétis, which solves the Navier-Stokes-Darcy-Brinkman equation using finite volumes, is expanded to take into account capillary pressures on the mesoscale. This formulation allows for more representativity than for Darcy's law (homogeneous preform) simulations while avoiding the prohibitive simulation times of a full discretization for the composing fibers at the representative elementary volume scale. The resulting tool is first used to investigate the effect of varying the slurry parameters on impregnation evolution. Two different processes, open bath impregnation and wet lay-up, are then studied with emphasis on varying their input parameters (e.g. inlet velocity).

Effect of ZnO on the Physical Properties and Optical Band Gap of Soda Lime Silicate Glass

PubMed Central

Zaid, Mohd Hafiz Mohd; Matori, Khamirul Amin; Aziz, Sidek Hj. Abdul; Zakaria, Azmi; Ghazali, Mohd Sabri Mohd

2012-01-01

This manuscript reports on the physical properties and optical band gap of five samples of soda lime silicate (SLS) glass combined with zinc oxide (ZnO) that were prepared by a melting and quenching process. To understand the role of ZnO in this glass structure, the density, molar volume and optical band gaps were investigated. The density and absorption spectra in the Ultra-Violet-Visible (UV-Visible) region were recorded at room temperature. The results show that the densities of the glass samples increased as the ZnO weight percentage increased. The molar volume of the glasses shows the same trend as the density: the molar volume increased as the ZnO content increased. The optical band gaps were calculated from the absorption edge, and it was found that the optical band gap decreased from 3.20 to 2.32 eV as the ZnO concentration increased. PMID:22837711

Abnormal trajectories in cerebellum and brainstem volumes in carriers of the fragile X premutation.

PubMed

Wang, Jun Yi; Hessl, David; Hagerman, Randi J; Simon, Tony J; Tassone, Flora; Ferrer, Emilio; Rivera, Susan M

2017-07-01

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder typically affecting male premutation carriers with 55-200 CGG trinucleotide repeat expansions in the FMR1 gene after age 50. The aim of this study was to examine whether cerebellar and brainstem changes emerge during development or aging in late life. We retrospectively analyzed magnetic resonance imaging scans from 322 males (age 8-81 years). Volume changes in the cerebellum and brainstem were contrasted with those in the ventricles and whole brain. Compared to the controls, premutation carriers without FXTAS showed significantly accelerated volume decrease in the cerebellum and whole brain, flatter inverted U-shaped trajectory of the brainstem, and larger ventricles. Compared to both older controls and premutation carriers without FXTAS, carriers with FXTAS exhibited significant volume decrease in the cerebellum and whole brain and accelerated volume decrease in the brainstem. We therefore conclude that cerebellar and brainstem volumes were likely affected during both development and progression of neurodegeneration in premutation carriers, suggesting that interventions may need to start early in adulthood to be most effective. Copyright © 2017 Elsevier Inc. All rights reserved.

The effects of horizontal body casting on blood volume, drug responsiveness, and +Gz tolerance in the rhesus monkey

NASA Technical Reports Server (NTRS)

Dickey, D. T.; Billman, G. E.; Teoh, K.; Sandler, H.; Stone, H. L.

1982-01-01

To simulate the weightless condition, eight rhesus monkeys, instrumented with solid-state pressure transducers, were horizontally restrained in body casts for 28 days. Blood volume decreased an average of 13% after 14 days of restraint, due mainly to a drop in plasma volume. Aortic pressure and heart rate responses to norepinephrine and phenylephrine decreased after 14 days of restraint. The monkeys did not show a statistically significant decreased tolerance to a 90 deg sudden upright tilt after horizontal restraint. During the fifth week of casting, four animals were subjected to +Gz acceleration tests on a centrifuge. The acceleration tolerance of the casted monkeys was significantly reduced compared to four similarly instrumented control animals. These findings indicate that the cardiovascular deconditioning associated with simulated weightlessness results from an inability to maintain central blood volume during orthostatic stress.

Metabolic bone disease in chronic renal failure. II. Renal transplant patients.

PubMed Central

Huffer, W. E.; Kuzela, D.; Popovtzer, M. M.; Starzl, T. E.

1975-01-01

Trabecular vertebral bone of renal transplant patients was quantitatively compared with bone from normal individuals and dialyzed and nondialyzed patienets with chronic renal failure reported in detail in an earlier study. Long- and short-term transplant patients have increased bone resorption and mineralization defects similar to renal osteodystrophy in dialyzed and nondialyzed patients. However, in transplant patients the magnitude of resorption is greater, and bone volume tends to decrease rather than increase. Resorptive activity in transplant patients is maximal during the first year after transplantation. Bone volume decreases continuously for at least 96 months after transplantation. Only decreased bone volume correlated with success or failure of the renal transplant. Morphologic findings in this study correlate with other clinical and morphologic data to suggest that reduction in bone volume in transplant patients results from a combination of persistent hyperparathyroidism and suppression of bone formation by steroid therapy. Images Fig 1 PMID:1091152

Decreasing Irradiated Rat Lung Volume Changes Dose-Limiting Toxicity From Early to Late Effects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Veen, Sonja J. van der; Faber, Hette; Ghobadi, Ghazaleh

2016-01-01

Purpose: Technological developments in radiation therapy result in smaller irradiated volumes of normal tissue. Because the risk of radiation therapy-induced toxicity generally depends on irradiated volume, changing volume could change the dose-limiting toxicity of a treatment. Recently, in our rat model, we found that early radiation-induced lung dysfunction (RILD) was closely related to irradiated volume dependent vascular remodeling besides inflammation. The exact relationship between early and late RILD is still unknown. Therefore, in this preclinical study we investigated the dose-volume relationship of late RILD, assessed its dependence on early and late pathologies and studied if decreasing irradiated volume changed themore » dose-limiting toxicity. Methods and Materials: A volume of 25%, 32%, 50%, 63%, 88%, or 100% of the rat lung was irradiated using protons. Until 26 weeks after irradiation, respiratory rates were measured. Macrovascular remodeling, pulmonary inflammation, and fibrosis were assessed at 26 weeks after irradiation. For all endpoints dose-volume response curves were made. These results were compared to our previously published early lung effects. Results: Early vascular remodeling and inflammation correlated significantly with early RILD. Late RILD correlated with inflammation and fibrosis, but not with vascular remodeling. In contrast to the early effects, late vascular remodeling, inflammation and fibrosis showed a primarily dose but not volume dependence. Comparison of respiratory rate increases early and late after irradiation for the different dose-distributions indicated that with decreasing irradiated volumes, the dose-limiting toxicity changed from early to late RILD. Conclusions: In our rat model, different pathologies underlie early and late RILD with different dose-volume dependencies. Consequently, the dose-limiting toxicity changed from early to late dysfunction when the irradiated volume was reduced. In patients, early and late RILD are also due to different pathologies. As such, new radiation techniques reducing irradiated volume might change the dose-limiting toxicity of the radiation therapy treatment.« less

Virginia's Forests

Treesearch

William A. Bechtold; Mark J. Brown; John B. Tansey

1987-01-01

Between 1977 and 1986, area of timberland in Virginia declined from 16.0 to 15.4 million acres. Volume of softwood growing stock increased by 5 percent, and volume of hardwood growing stock increased by 11 percent. Softwood net annual growth decreased by 7 percent, and hardwood growing-stick growth decreased by 1 percent. Softwood removals remained almost unchanged...

[Pulmonary function in patients with infiltrative pulmonary tuberculosis].

PubMed

Nefedov, V B; Popova, L A; Shergina, E A

2007-01-01

Vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/VC%, PEF, MEF25, MEF50, MEF75, TLC, TGV, pulmonary residual volume (PRV), R(aw), R(in),, R(ex), DLCO-SB, DLCO-SS, PaO2, and PaCO2 were determined in 103 patients with infiltrative pulmonary tuberculosis. Pulmonary dysfunction was detected in 83.5% of the patients. Changes were found in lung volumes and capacities in 63.1%, impaired bronchial patency and pulmonary gas exchange dysfunction were in 60.2 and 41.7%, respectively. The changes in pulmonary volumes and capacities appeared as increased PRV, decreased VC and FVC, and decreased and increased TGV and TLC; impaired bronchial patency presented as decreased PEF, MEF25, MEF50, MEF75, FEV1/VC% and increased R(aw) R(in), and R(ex); pulmonary gas exchange dysfunction manifested itself as reduced DLCO-SB, DLCO-SS, and PaO2 and decreased and increased PaCO2. The magnitude of the observed functional changes was generally slight. Significant disorders were observed rarely and very pronounced ones were exceptional.

[Pulmonary function in patients with disseminated pulmonary tuberculosis].

PubMed

Nefedov, V B; Shergina, E A; Popova, L A

2007-01-01

Vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/VC%, PEF, MEF25%, MEF50%, MEF75%, TLS, TGV, pulmonary residual volume (PRV), Raw, Rin, Rex, DLCO-SB, DLCO-SS, PaO2, and PaCO2 were determined in 29 patients with disseminated pulmonary tuberculosis. Pulmonary dysfunction was detected in 93.1% of the patients. Changes were found in lung volumes and capacities in 65.5%, impaired bronchial patency and pulmonary gas exchange dysfunction were in 79.3 and 37.9%, respectively. The changes in pulmonary volumes and capacities appeared as increased PRV, decreased VC, FVC, and TLS, decreased and increased TGV; impaired bronchial patency presented as decreased PEF, MEF25%, MEF50%, MEF75%, and FEV1/VC% and increased Raw, Rin, and Rex; pulmonary gas exchange dysfunction manifested itself as reduced DLCO-SS and PaO2 and decreased and increased PaCO2. The observed functional changes varied from slight to significant and pronounced with a preponderance of small disorders, a lower detection rate of significant disorders, and rare detection of very pronounced ones.

Bernoulli Suction Effect on Soap Bubble Blowing?

NASA Astrophysics Data System (ADS)

Davidson, John; Ryu, Sangjin

2015-11-01

As a model system for thin-film bubble with two gas-liquid interfaces, we experimentally investigated the pinch-off of soap bubble blowing. Using the lab-built bubble blower and high-speed videography, we have found that the scaling law exponent of soap bubble pinch-off is 2/3, which is similar to that of soap film bridge. Because air flowed through the decreasing neck of soap film tube, we studied possible Bernoulli suction effect on soap bubble pinch-off by evaluating the Reynolds number of airflow. Image processing was utilized to calculate approximate volume of growing soap film tube and the volume flow rate of the airflow, and the Reynolds number was estimated to be 800-3200. This result suggests that soap bubbling may involve the Bernoulli suction effect.

Amygdala and hippocampus volumes are differently affected by childhood trauma in patients with bipolar disorders and healthy controls.

PubMed

Janiri, Delfina; Sani, Gabriele; Rossi, Pietro De; Piras, Fabrizio; Iorio, Mariangela; Banaj, Nerisa; Giuseppin, Giulia; Spinazzola, Edoardo; Maggiora, Matteo; Ambrosi, Elisa; Simonetti, Alessio; Spalletta, Gianfranco

2017-08-01

Volumetric studies on deep gray matter structures in bipolar disorder (BP) have reported contrasting results. Childhood trauma, a relevant environmental stressor for BP, could account for the variability of the results, modulating differences in the amygdala and hippocampus in patients with BP compared with healthy controls (HC). Our study aimed to test this hypothesis. We assessed 105 outpatients, diagnosed with bipolar disorder type I (BP-I) or bipolar disorder type II (BP-II) according to DSM-IV-TR criteria, and 113 HC subjects. History of childhood trauma was obtained using the Childhood Trauma Questionnaire (CTQ). High-resolution magnetic resonance imaging was performed on all subjects and volumes of the amygdala, hippocampus, nucleus accumbens, caudate, pallidum, putamen, and thalamus were measured using FreeSurfer. Patients with BP showed a global reduction of deep gray matter volumes compared to HCs. However, childhood trauma modulated the impact of the diagnosis specifically on the amygdala and hippocampus. Childhood trauma was associated with bilateral decreased volumes in HCs and increased volumes in patients with BP. The results suggest that childhood trauma may have a different effect in health and disease on volumes of gray matter in the amygdala and hippocampus, which are brain areas specifically involved in response to stress and emotion processing. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Infratemporal fossa fat enlargement in chronic maxillary atelectasis.

PubMed

Kohn, Jocelyne C; Rootman, Daniel B; Xu, Dongdong; Goldberg, Robert A

2013-08-01

To describe the radiographic findings in chronic maxillary atelectasis and analyse the volume changes of the affected maxillary sinus, orbit, nasal vault and infratemporal fossa. Case series of all patients with diagnosis of chronic maxillary atelectasis presenting between January 2000 and August 2012 who underwent full oculoplastic and orbital evaluation including standardised photography and CT or MRI. Two-dimensional imaging features and volumetric changes were assessed. Affected and unaffected sides were compared. Demographic data, clinical presentation, Hertel measurements, photographic and radiological findings were analysed. 22 patients (64% men) met the inclusion criteria. Mean relative enophthalmos was 2.1 mm and mean hypoglobus was 1.8 mm. The most common radiographic findings were sinus opacification (91%), uncinate process retraction/middle meatus increase (91%), orbit enlargement (100%), ipsilateral septum deviation (64%) and infratemporal fossa fat enlargement (100%). Infratemporal fossa fat area and volume were significantly larger in the affected side (p<0.01). Additionally, ipsilateral orbit (p<0.01) and nasal vault volume (p<0.01) were similarly increased. Maxillary sinus volume correlated significantly only with infratemporal fossa fat enlargement (p<0.05). There is a significant increase in the infratemporal fossa fat, nasal and orbital volume corresponding to a decrease in maxillary sinus size in chronic maxillary atelectasis. Chronic maxillary atelectasis is associated with redistribution of volume between the maxillary sinus and the surrounding infratemporal fossa, orbit and nasal cavity.

Tailoring rice flour structure by rubbery milling for improved gluten-free baked goods.

PubMed

Brütsch, Linda; Tribolet, Liliane; Isabettini, Stéphane; Soltermann, Patrick; Baumann, Andreas; Windhab, Erich J

2018-05-10

Ever-growing demand for gluten-free products calls for the development of novel food processing techniques to widen the range of existing baked goods. Extensive research has been targeted towards recipe optimization, widely neglecting the tailoring potential of process-induced structuring of gluten-free raw materials. Herein, we address this shortcoming by demonstrating the potential of rubbery milling for the generation of structure and techno-functionality in breads obtained from a variety of rice flour types. Moisture and temperature induced state transitions during milling were exploited to tailor the physicochemical properties of the flour. Moisture addition during conditioning of the different rice varieties and milling in the rubbery state considerably decreased starch damage due to more gentle disintegration. The degree of starch damage dictated the water absorption capacity of the rice flour types. Flour types with reduced starch damage upon milling offered lower dough densities, yielding bread loafs with a higher volume and better appearance. The choice of rice variety enables fine-tuning of the final product quality by influencing the dough viscoelasticity, which defines the final loaf volume. Whole grain rice flour dramatically increased the loaf volume, whilst simultaneously offering nutritional benefits. Combining the proposed functionalised flour types with current and future advances in product recipes paves the way towards optimised gluten-free goods.

Respiratory Pattern and Tidal Volumes Differ for Pressure Support and Volume-assured Pressure Support in Amyotrophic Lateral Sclerosis.

PubMed

Nicholson, Trevor T; Smith, Sean B; Siddique, Teepu; Sufit, Robert; Ajroud-Driss, Senda; Coleman, John M; Wolfe, Lisa F

2017-07-01

Amyotrophic lateral sclerosis (ALS) is a progressive neuromuscular disease resulting in respiratory failure and death. Use of noninvasive ventilation (NIV) improves survival. However, use of volume-assured pressure support (VAPS) has not been extensively studied in ALS. To explore the clinical usefulness of a detailed evaluation of device-recorded NIV data in the management of chronic respiratory failure in ALS, and to determine whether there are differences in efficacy between patients using VAPS or PS. We performed a retrospective chart review of 271 patients with ALS using either PS or VAPS, along with an evaluation of device-recorded data to explore differences in attainment of goal tidal volumes (Vt) and ratio of respiratory rate to tidal volume (f/Vt), in addition to triggering and cycling ability. Two hundred and fifteen patients were using PS, while 56 were using VAPS. There were no significant differences in demographic data, symptoms, pulmonary function, or patient compliance. Compared with VAPS, achieved Vt was significantly lower for PS while f/Vt was significantly higher. Percent spontaneous triggering was relatively preserved in both cohorts, whereas percent spontaneous cycling was considerably decreased in both. Furthermore, there was no association found between spontaneous triggering or cycling, and pulmonary function, indicating the presence of low spontaneous breath cycling or triggering ability is difficult to predict. Examination of device data for exhaled tidal volumes and f/Vt may be of use in evaluating efficacy of NIV in ALS. VAPS provides more reliable goal Vt than does PS, and is associated with decreased f/Vt. Spontaneous cycling is decreased in ALS despite preservation of triggering ability. Although a set backup rate may address decreased triggering, perhaps more importantly, setting a sufficient fixed inspiratory time would address the issue of decreased cycling.

Activin-A, transforming growth factor-beta, and myostatin signaling pathway in experimental dilated cardiomyopathy.

PubMed

Mahmoudabady, Maryam; Mathieu, Myrielle; Dewachter, Laurence; Hadad, Ielham; Ray, Lynn; Jespers, Pascale; Brimioulle, Serge; Naeije, Robert; McEntee, Kathleen

2008-10-01

The pathogenic mechanisms of dilated cardiomyopathy are still uncertain. A number of cytokines and growth factors participate in the remodeling process of the disease. We investigated the cardiac myostatin, transforming growth factor (TGF)beta, and activin-A/Smad growth inhibitory signaling pathway in experimental dilated cardiomyopathy. Transvenous endomyocardial biopsies of the interventricular septum were taken weekly in 15 beagle dogs during the development of heart failure (HF) induced by rapid pacing over a period of 7 weeks. Genes involved in the myostatin-TGFbeta-activin-A/Smad signaling pathway and the cardiac hypertrophic process were quantified by real-time quantitative polymerase chain reaction. Left ventricular volume, function, and mass were evaluated by echocardiography. Overpacing was associated with increased left ventricular volumes and decreased ejection fraction, whereas the left ventricular mass remained unchanged. TGFbeta was increased in moderate HF. Activin-A mRNA expression was 4-fold higher in overt congestive HF than at baseline. A 2-fold decrease of activin type II receptors and activin receptor interacting protein 2 gene expressions were observed, as well as a transient decrease of follistatin. Activin type I receptors, activin receptor interacting protein 1, follistatin-related gene, and myostatin remained unchanged. The inhibitory Smad 7, a negative feedback loop regulator of the Smad pathway, was overexpressed in severe HF. Gene expression of the cyclin-dependent kinase inhibitor p21, a direct target gene of the Smad pathway, was 8-fold up-regulated in HF, whereas cyclin D1 was down-regulated. We conclude that tachycardia-induced dilated cardiomyopathy is characterized by gene overexpression of the TGFbeta-activin-A/Smad signaling pathway and their target gene p21 and by the absence of ventricular hypertrophy.

Effect of Boron Addition on the Thermal, Degradation, and Cytocompatibility Properties of Phosphate-Based Glasses

PubMed Central

Hasan, Muhammad S.; Parsons, Andrew J.; Furniss, David; Scotchford, Colin A.; Ahmed, Ifty; Rudd, Chris D.

2013-01-01

In this study eight different phosphate-based glass compositions were prepared by melt-quenching: four in the (P2O5)45-(CaO)16-(Na2O)15-x -(MgO)24-(B2O3)x system and four in the system (P2O5)50-(CaO)16-(Na2O)10-x-(MgO)24-(B2O3)x, where x = 0,1, 5 and 10 mol%. The effect of B2O3 addition on the thermal properties, density, molar volume, dissolution rates, and cytocompatibility were studied for both glass systems. Addition of B2O3 increased the glass transition (T g), crystallisation (T c), melting (T m), Liquidus (T L) and dilatometric softening (T d) temperature and molar volume (V m). The thermal expansion coefficient (α) and density (ρ) were seen to decrease. An assessment of the thermal stability of the glasses was made in terms of their processing window (crystallisation onset, T c,ons minus glass transition temperature, T g), and an increase in the processing window was observed with increasing B2O3 content. Degradation studies of the glasses revealed that the rates decreased with increasing B2O3 content and a decrease in degradation rates was also observed as the P2O5 content reduced from 50 to 45 mol%. MG63 osteoblast-like cells cultured in direct contact with the glass samples for 14 days revealed comparative data to the positive control for the cell metabolic activity, proliferation, ALP activity, and morphology for glasses containing up to 5 mol% of B2O3. PMID:23991425

TiO2 film properties as a function of processing temperature, volume 3

NASA Technical Reports Server (NTRS)

Fitzgibbons, E. T.; Sladek, K. J.; Hartwig, W. H.

1972-01-01

Thin film TiO2 was produced at 150 C by chemical vapor deposition using hydrolysis of tetraisopropyl titanate. Films were amorphous as grown, but annealing in air caused crystallization, with anatase formed beginning at 350 C and rutile at 700 C. Density and index of refraction increased substantially with increasing anneal temperature, while etch susceptibility in HF and H2SO4 decreased. Comparison with literature data showed two groups of processes. One group yields films having properties that gradually approach those of rutile with increasing process temperature. The other group gives rutile directly at moderate temperatures. Deposition of amorphous film followed by etching and annealing is suggested as a means for pattern definition.

Impact of Depression, Fatigue, and Global Measure of Cortical Volume on Cognitive Impairment in Multiple Sclerosis

PubMed Central

De Cola, Maria Cristina; D'Aleo, Giangaetano; Sessa, Edoardo; Marino, Silvia

2015-01-01

Objective. To investigate the influence of demographic and clinical variables, such as depression, fatigue, and quantitative MRI marker on cognitive performances in a sample of patients affected by multiple sclerosis (MS). Methods. 60 MS patients (52 relapsing remitting and 8 primary progressive) underwent neuropsychological assessments using Rao's Brief Repeatable Battery of Neuropsychological Tests (BRB-N), the Beck Depression Inventory-second edition (BDI-II), and the Fatigue Severity Scale (FSS). We performed magnetic resonance imaging to all subjects using a 3 T scanner and obtained tissue-specific volumes (normalized brain volume and cortical brain volume). We used Student's t-test to compare depressed and nondepressed MS patients. Finally, we performed a multivariate regression analysis in order to assess possible predictors of patients' cognitive outcome among demographic and clinical variables. Results. 27.12% of the sample (16/59) was cognitively impaired, especially in tasks requiring attention and information processing speed. From between group comparison, we find that depressed patients had worse performances on BRB-N score, greater disability and disease duration, and brain volume decrease. According to multiple regression analysis, the BDI-II score was a significant predictor for most of the neuropsychological tests. Conclusions. Our findings suggest that the presence of depressive symptoms is an important determinant of cognitive performance in MS patients. PMID:25861633

Decision-making deficit of a patient with axonal damage after traumatic brain injury.

PubMed

Yasuno, Fumihiko; Matsuoka, Kiwamu; Kitamura, Soichiro; Kiuchi, Kuniaki; Kosaka, Jun; Okada, Koji; Tanaka, Syohei; Shinkai, Takayuki; Taoka, Toshiaki; Kishimoto, Toshifumi

2014-02-01

Patients with traumatic brain injury (TBI) were reported to have difficulty making advantageous decisions, but the underlying deficits of the network of brain areas involved in this process were not directly examined. We report a patient with TBI who demonstrated problematic behavior in situations of risk and complexity after cerebral injury from a traffic accident. The Iowa gambling task (IGT) was used to reveal his deficits in the decision-making process. To examine underlying deficits of the network of brain areas, we examined T1-weighted structural MRI, diffusion tensor imaging (DTI) and Tc-ECD SPECT in this patient. The patient showed abnormality in IGT. DTI-MRI results showed a significant decrease in fractional anisotropy (FA) in the fasciculus between the brain stem and cortical regions via the thalamus. He showed significant decrease in gray matter volumes in the bilateral insular cortex, hypothalamus, and posterior cingulate cortex, possibly reflecting Wallerian degeneration secondary to the fasciculus abnormalities. SPECT showed significant blood flow decrease in the broad cortical areas including the ventromedial prefrontal cortex (VM). Our study showed that the patient had dysfunctional decision-making process. Microstructural abnormality in the fasciculus, likely from the traffic accident, caused reduced afferent feedback to the brain, resulting in less efficient decision-making. Our findings support the somatic-marker hypothesis (SMH), where somatic feedback to the brain influences the decision-making process. Copyright © 2013 Elsevier Inc. All rights reserved.

Effects of sex chromosome aneuploidies on brain development: evidence from neuroimaging studies.

PubMed

Lenroot, Rhoshel K; Lee, Nancy Raitano; Giedd, Jay N

2009-01-01

Variation in the number of sex chromosomes is a relatively common genetic condition, affecting as many as 1/400 individuals. The sex chromosome aneuploidies (SCAs) are associated with characteristic behavioral and cognitive phenotypes, although the degree to which specific individuals are affected can fall within a wide range. Understanding the effects of different dosages of sex chromosome genes on brain development may help to understand the basis for functional differences in affected individuals. It may also be informative regarding how sex chromosomes contribute to typical sexual differentiation. Studies of 47,XXY males make up the bulk of the current literature of neuroimaging studies in individuals with supernumerary sex chromosomes, with a few small studies or case reports of the other SCAs. Findings in 47,XXY males typically include decreased gray and white matter volumes, with most pronounced effects in the frontal and temporal lobes. Functional studies have shown evidence of decreased lateralization. Although the hypogonadism typically found in 47,XXY males may contribute to the decreased brain volume, the observation that 47,XXX females also show decreased brain volume in the presence of normal pubertal maturation suggests a possible direct dosage effect of X chromosome genes. Additional X chromosomes, such as in 49,XXXXY males, are associated with more markedly decreased brain volume and increased incidence of white matter hyperintensities. The limited data regarding effects of having two Y chromosomes (47,XYY) do not find significant differences in brain volume, although there are some reports of increased head size.

Effects of Sex Chromosome Aneuploidies on Brain Development: Evidence From Neuroimaging Studies

PubMed Central

Lenroot, Rhoshel K.; Lee, Nancy Raitano; Giedd, Jay N.

2010-01-01

Variation in the number of sex chromosomes is a relatively common genetic condition, affecting as many as 1/400 individuals. The sex chromosome aneuploidies (SCAs) are associated with characteristic behavioral and cognitive phenotypes, although the degree to which specific individuals are affected can fall within a wide range. Understanding the effects of different dosages of sex chromosome genes on brain development may help to understand the basis for functional differences in affected individuals. It may also be informative regarding how sex chromosomes contribute to typical sexual differentiation. Studies of 47,XXY males make up the bulk of the current literature of neuroimaging studies in individuals with supernumerary sex chromosomes, with a few small studies or case reports of the other SCAs. Findings in 47,XXY males typically include decreased gray and white matter volumes, with most pronounced effects in the frontal and temporal lobes. Functional studies have shown evidence of decreased lateralization. Although the hypogonadism typically found in 47,XXY males may contribute to the decreased brain volume, the observation that 47,XXX females also show decreased brain volume in the presence of normal pubertal maturation suggests a possible direct dosage effect of X chromosome genes. Additional X chromosomes, such as in 49,XXXXY males, are associated with more markedly decreased brain volume and increased incidence of white matter hyperintensities. The limited data regarding effects of having two Y chromosomes (47,XYY) do not find significant differences in brain volume, although there are some reports of increased head size. PMID:20014372

FSI simulation of CSF hydrodynamic changes in a large population of non-communicating hydrocephalus patients during treatment process with regard to their clinical symptoms

PubMed Central

2018-01-01

3D fluid-structure interaction modelling was utilized for simulation of 13 normal subjects, 11 non-communicating hydrocephalus (NCH) patients at pre-treatment phase, and 3 patients at five post-treatment phases. Evaluation of ventricles volume and maximum CSF pressure (before shunting) following results validation indicated that these parameters were the most proper hydrodynamic indices and the NCH type doesn’t have any significant effect on changes in two indices. The results confirmed an appropriate correlation between these indices although the correlation decreased slightly after the occurrence of disease. NCH raises the intensity of vortex and pulsatility (2.4 times) of CSF flow while the flow remains laminar. On day 18 after shunting, the CSF pressure decreased 81.0% and all clinical symptoms of patients vanished except for headache. Continuing this investigation during the treatment process showed that maximum CSF pressure is the most sensitive parameter to patients’ clinical symptoms. Maximum CSF pressure has decreased proportional to the level of decrease in clinical symptoms and has returned close to the pressure range in normal subjects faster than other parameters and simultaneous with disappearance of patients’ clinical symptoms (from day 81 after shunting). However, phase lag between flow rate and pressure gradient functions and the degree of CSF pulsatility haven’t returned to normal subjects’ conditions even 981 days after shunting and NCH has also caused a permanent volume change (of 20.1%) in ventricles. Therefore, patients have experienced a new healthy state in new hydrodynamic conditions after shunting and healing. Increase in patients’ intracranial compliance was predicted with a more accurate non-invasive method than previous experimental methods up to more than 981 days after shunting. The changes in hydrodynamic parameters along with clinical reports of patients can help to gain more insight into the pathophysiology of NCH patients. PMID:29708982

Changes in Search Path Complexity and Length During Learning of a Virtual Water Maze: Age Differences and Differential Associations with Hippocampal Subfield Volumes.

PubMed

Daugherty, Ana M; Bender, Andrew R; Yuan, Peng; Raz, Naftali

2016-06-01

Impairment of hippocampus-dependent cognitive processes has been proposed to underlie age-related deficits in navigation. Animal studies suggest a differential role of hippocampal subfields in various aspects of navigation, but that hypothesis has not been tested in humans. In this study, we examined the association between volume of hippocampal subfields and age differences in virtual spatial navigation. In a sample of 65 healthy adults (age 19-75 years), advanced age was associated with a slower rate of improvement operationalized as shortening of the search path over 25 learning trials on a virtual Morris water maze task. The deficits were partially explained by greater complexity of older adults' search paths. Larger subiculum and entorhinal cortex volumes were associated with a faster decrease in search path complexity, which in turn explained faster shortening of search distance. Larger Cornu Ammonis (CA)1-2 volume was associated with faster distance shortening, but not in path complexity reduction. Age differences in regional volumes collectively accounted for 23% of the age-related variance in navigation learning. Independent of subfield volumes, advanced age was associated with poorer performance across all trials, even after reaching the asymptote. Thus, subiculum and CA1-2 volumes were associated with speed of acquisition, but not magnitude of gains in virtual maze navigation. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Growth of the Maize Primary Root at Low Water Potentials 1

PubMed Central

Sharp, Robert E.; Hsiao, Theodore C.; Silk, Wendy Kuhn

1990-01-01

Primary roots of maize (Zea mays L. cv WF9 × Mo17) seedlings growing in vermiculite at various water potentials exhibited substantial osmotic adjustment in the growing region. We have assessed quantitatively whether the osmotic adjustment was attributable to increased net solute deposition rates or to slower rates of water deposition associated with reduced volume expansion. Spatial distributions of total osmotica, soluble carbohydrates, potassium, and water were combined with published growth velocity distributions to calculate deposition rate profiles using the continuity equation. Low water potentials had no effect on the rate of total osmoticum deposition per unit length close to the apex, and caused decreased deposition rates in basal regions. However, rates of water deposition decreased more than osmoticum deposition. Consequently, osmoticum deposition rates per unit water volume were increased near the apex and osmotic potentials were lower throughout the growing region. Because the stressed roots were thinner, osmotic adjustment occurred without osmoticum accumulation per unit length. The effects of low water potential on hexose deposition were similar to those for total osmotica, and hexose made a major contribution to the osmotic adjustment in middle and basal regions. In contrast, potassium deposition decreased at low water potentials in close parallel with water deposition, and increases in potassium concentration were small. The results show that growth of the maize primary root at low water potentials involves a complex pattern of morphogenic and metabolic events. Although osmotic adjustment is largely the result of a greater inhibition of volume expansion and water deposition than solute deposition, the contrasting behavior of hexose and potassium deposition indicates that the adjustment is a highly regulated process. PMID:16667622

Thalamic white matter in multiple sclerosis: A combined diffusion-tensor imaging and quantitative susceptibility mapping study.

PubMed

Bergsland, Niels; Schweser, Ferdinand; Dwyer, Michael G; Weinstock-Guttman, Bianca; Benedict, Ralph H B; Zivadinov, Robert

2018-06-19

Thalamic white matter (WM) injury in multiple sclerosis (MS) remains relatively poorly understood. Combining multiple imaging modalities, sensitive to different tissue properties, may aid in further characterizing thalamic damage. Forty-five MS patients and 17 demographically-matched healthy controls (HC) were scanned with 3T MRI to obtain quantitative measures of diffusivity and magnetic susceptibility. Participants underwent cognitive evaluation with the Brief International Cognitive Assessment for Multiple Sclerosis battery. Tract-based spatial statistics identified thalamic WM. Non-parametric combination (NPC) analysis was used to perform joint inference on fractional anisotropy (FA), mean diffusivity (MD) and magnetic susceptibility measures. The association of surrounding WM lesions and thalamic WM pathology was investigated with lesion probability mapping. Compared to HCs, the greatest extent of thalamic WM damage was reflected by the combination of increased MD and decreased magnetic susceptibility (63.0% of thalamic WM, peak p = .001). Controlling for thalamic volume resulted in decreased FA and magnetic susceptibility (34.1%, peak p = .004) as showing the greatest extent. In MS patients, the most widespread association with information processing speed was found with the combination of MD and magnetic susceptibility (67.6%, peak p = .0005), although this was not evident after controlling for thalamic volume. For memory measures, MD alone yielded the most widespread associations (45.9%, peak p = .012 or 76.7%, peak p = .001), even after considering thalamic volume, albeit with smaller percentages. White matter lesions were related to decreased FA (peak p = .0063) and increased MD (peak p = .007), but not magnetic susceptibility, of thalamic WM. Our study highlights the complex nature of thalamic pathology in MS. © 2018 Wiley Periodicals, Inc.

Fracture healing with alendronate treatment in the Brtl/+ mouse model of osteogenesis imperfecta

PubMed Central

Meganck, J.A.; Begun, D.L.; McElderry, J.D.; Swick, A.; Kozloff, K.M.; Goldstein, S.A.; Morris, M.D.; Marini, J.C.; Caird, M.S.

2014-01-01

Osteogenesis imperfecta (OI) is a heritable bone dysplasia characterized by increased skeletal fragility. Patients are often treated with bisphosphonates to attempt to reduce fracture risk. However, bisphosphonates reside in the skeleton for many years and long-term administration may impact bone material quality. Acutely, there is concern about risk of non-union of fractures that occur near the time of bisphosphonate administration. This study investigated the effect of alendronate, a potent aminobisphosphonate, on fracture healing. Using the Brtl/+ murine model of type IV OI, tibial fractures were generated in 8-week-old mice that were untreated, treated with alendronate before fracture, or treated before and after fracture. After 2, 3, or 5 weeks of healing, tibiae were assessed using microcomputed tomography (μCT), torsion testing, quantitative histomorphometry, and Raman microspectroscopy. There were no morphologic, biomechanical or histomorphometric differences in callus between untreated mice and mice that received alendronate before fracture. Alendronate treatment before fracture did not cause a significant increase in cartilage retention in fracture callus. Both Brtl/+ and WT mice that received alendronate before and after fracture had increases in the callus volume, bone volume fraction and torque at failure after 5 weeks of healing. Raman microspectroscopy results did not show any effects of alendronate in wild-type mice, but calluses from Brtl/+ mice treated with alendronate during healing had a decreased mineral-to-matrix ratio, decreased crystallinity and an increased carbonate-to-phosphate ratio. Treatment with alendronate altered the dynamics of healing by preventing callus volume decreases later in the healing process. Fracture healing in Brtl/+ untreated animals was not significantly different from animals in which alendronate was halted at the time of fracture. PMID:23774443

Optic coherence tomography shows inflammation and degeneration in major depressive disorder patients correlated with disease severity.

PubMed

Kalenderoglu, Aysun; Çelik, Mustafa; Sevgi-Karadag, Ayse; Egilmez, Oguzhan Bekir

2016-11-01

Previous research has consistently detected inflammation in the etiology of depression and neuroimaging studies have demonstrated gray matter abnormalities implying a neurodegenerative process in depression. The aim of this study was to compare ganglion cell layer (GCL), and inner plexiform layer (IPL) volumes and retinal nerve fiber layer (RNFL) thickness between first episode and recurrent major depressive disorder (MDD) patients and controls using optic coherence tomography (OCT) in order to detect findings supporting a degenerative process. Also choroid thicknesses of the same groups were compared to examine effects of inflammation on MDD. This study included 50 recurrent MDD patients, 50 first episode MDD patients and 50 controls. OCT measurements were performed by a spectral OCT device. GCL and IPL volumes and RNFL and choroid thicknesses were measured automatically by the device. GCL and IPL volumes were significantly smaller in recurrent depression patients than first episode patients and in all MDD patients than controls. Also there were significant negative correlations between their volumes and disease severity parameters such as Ham-D and CGI scores, and disease duration. RNFL thicknesses were also lower in recurrent MDD patients than first episode patients and all MDD patients than controls but statistical significance was achieved only for global RNFL and temporal superior RNFL. Mean choroid thickness was higher in MDD patients than controls and in first episode MDD patients than recurrent MDD patients. Cross-sectional design of our study limits conclusions about progressive degeneration during the course of MDD. Lack of a control neuroimaging method like magnetic resonance imaging makes it hard to draw firm conclusions from our results. OCT finding of decreased GCL and IPL volumes supports previous research suggesting degeneration in MDD. OCT may be an important tool to track neurodegeneration in patients with major depression. Considering RNFL to be the latest layer that will be affected during course of degeneration, GCL and IPL volumes appear to be better parameters to follow. In addition, choroid may be an important structure to detect acute attack period and to follow inflammatory process in MDD like in systemic inflammatory diseases. Copyright © 2016 Elsevier B.V. All rights reserved.

Structural neuroplasticity in the sensorimotor network of professional female ballet dancers.

PubMed

Hänggi, Jürgen; Koeneke, Susan; Bezzola, Ladina; Jäncke, Lutz

2010-08-01

Evidence suggests that motor, sensory, and cognitive training modulates brain structures involved in a specific practice. Functional neuroimaging revealed key brain structures involved in dancing such as the putamen and the premotor cortex. Intensive ballet dance training was expected to modulate the structures of the sensorimotor network, for example, the putamen, premotor cortex, supplementary motor area (SMA), and the corticospinal tracts. We investigated gray (GM) and white matter (WM) volumes, fractional anisotropy (FA), and mean diffusivity (MD) using magnetic resonance-based morphometry and diffusion tensor imaging in 10 professional female ballet dancers compared with 10 nondancers. In dancers compared with nondancers, decreased GM volumes were observed in the left premotor cortex, SMA, putamen, and superior frontal gyrus, and decreased WM volumes in both corticospinal tracts, both internal capsules, corpus callosum, and left anterior cingulum. FA was lower in the WM underlying the dancers' left and right premotor cortex. There were no significant differences in MD between the groups. Age of dance commencement was negatively correlated with GM and WM volume in the right premotor cortex and internal capsule, respectively, and positively correlated with WM volume in the left precentral gyrus and corpus callosum. Results were not influenced by the significantly lower body mass index of the dancers. The present findings complement the results of functional imaging studies in experts that revealed reduced neural activity in skilled compared with nonskilled subjects. Reductions in brain activity are accompanied by local decreases in GM and WM volumes and decreased FA. 2009 Wiley-Liss, Inc.

TU-H-CAMPUS-JeP3-02: Automated Dose Accumulation and Dose Accuracy Assessment for Online Or Offline Adaptive Replanning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, G; Ahunbay, E; Li, X

Purpose: With introduction of high-quality treatment imaging during radiation therapy (RT) delivery, e.g., MR-Linac, adaptive replanning of either online or offline becomes appealing. Dose accumulation of delivered fractions, a prerequisite for the adaptive replanning, can be cumbersome and inaccurate. The purpose of this work is to develop an automated process to accumulate daily doses and to assess the dose accumulation accuracy voxel-by-voxel for adaptive replanning. Methods: The process includes the following main steps: 1) reconstructing daily dose for each delivered fraction with a treatment planning system (Monaco, Elekta) based on the daily images using machine delivery log file and consideringmore » patient repositioning if applicable, 2) overlaying the daily dose to the planning image based on deformable image registering (DIR) (ADMIRE, Elekta), 3) assessing voxel dose deformation accuracy based on deformation field using predetermined criteria, and 4) outputting accumulated dose and dose-accuracy volume histograms and parameters. Daily CTs acquired using a CT-on-rails during routine CT-guided RT for sample patients with head and neck and prostate cancers were used to test the process. Results: Daily and accumulated doses (dose-volume histograms, etc) along with their accuracies (dose-accuracy volume histogram) can be robustly generated using the proposed process. The test data for a head and neck cancer case shows that the gross tumor volume decreased by 20% towards the end of treatment course, and the parotid gland mean dose increased by 10%. Such information would trigger adaptive replanning for the subsequent fractions. The voxel-based accuracy in the accumulated dose showed that errors in accumulated dose near rigid structures were small. Conclusion: A procedure as well as necessary tools to automatically accumulate daily dose and assess dose accumulation accuracy is developed and is useful for adaptive replanning. Partially supported by Elekta, Inc.« less

Processing Science of Advanced Ceramics. Materials Research Society Symposium Proceedings. Volume 155

DTIC Science & Technology

1990-09-01

can see that as the particle diameter ratio decreased more from unity, the freezing curve in the D - x phase diagram begins to show a maximum with...predicted for the rod area fraction of 0.26. Free energy curves for the two phases are shown as a function of rod concentration. The random phise has lower...fabrication techniques leing used range from consolidation of subinicron-sized powders to vapor phase deposition. ’hc papers included in this

Decreased frontal white-matter volume in chronic substance abuse.

PubMed

Schlaepfer, Thomas E; Lancaster, Eric; Heidbreder, Rebecca; Strain, Eric C; Kosel, Markus; Fisch, Hans-Ulrich; Pearlson, Godfrey D

2006-04-01

There is quite a body of work assessing functional brain changes in chronic substance abuse, much less is known about structural brain abnormalities in this patient population. In this study we used magnetic resonance imaging (MRI) to determine if structural brain differences exist in patients abusing illicit drugs compared to healthy controls. Sixteen substance abusers who abused heroin, cocaine and cannabis but not alcohol and 16 age-, sex- and race-matched controls were imaged on a MRI scanner. Contiguous, 5-mm-thick axial slices were acquired with simultaneous T2 and proton density sequences. Volumes were estimated for total grey and white matter, frontal grey and white matter, ventricles, and CSF using two different methods: a conventional segmentation and a stereological method based on the Cavalieri principle. Overall brain volume differences were corrected for by expressing the volumes of interest as a percentage of total brain volume. Volume measures obtained with the two methods were highly correlated (r=0.65, p<0.001). Substance abusers had significantly less frontal white-matter volume percentage than controls. There were no significant differences in any of the other brain volumes measured. This difference in frontal lobe white matter might be explained by a direct neurotoxic effect of drug use on white matter, a pre-existing abnormality in the development of the frontal lobe or a combination of both effects. This last explanation might be compelling based on the fact that newer concepts on shared aspects of some neuropsychiatric disorders focus on the promotion and inhibition of the process of myelination throughout brain development and subsequent degeneration.

Emotion recognition and theory of mind are related to gray matter volume of the prefrontal cortex in schizophrenia.

PubMed

Maat, Arija; van Haren, Neeltje E M; Bartholomeusz, Cali F; Kahn, René S; Cahn, Wiepke

2016-02-01

Investigations of social cognition in schizophrenia have demonstrated consistent impairments compared to healthy controls. Functional imaging studies in schizophrenia patients and healthy controls have revealed that social cognitive processing depends critically on the amygdala and the prefrontal cortex (PFC). However, the relationship between social cognition and structural brain abnormalities in these regions in schizophrenia patients is less well understood. Measures of facial emotion recognition and theory of mind (ToM), two key social cognitive abilities, as well as face perception and IQ, were assessed in 166 patients with schizophrenia and 134 healthy controls. MRI brain scans were acquired. Automated parcellation of the brain to determine gray matter volume of the amygdala and the superior, middle, inferior and orbital PFC was performed. Between-group analyses showed poorer recognition of angry faces and ToM performance, and decreased amygdala and PFC gray matter volumes in schizophrenia patients as compared to healthy controls. Moreover, in schizophrenia patients, recognition of angry faces was associated with inferior PFC gray matter volume, particularly the pars triangularis (p=0.006), with poor performance being related to reduced pars triangularis gray matter volume. In addition, ToM ability was related to PFC gray matter volume, particularly middle PFC (p=0.001), in that poor ToM skills in schizophrenia patients were associated with reduced middle PFC gray matter volume. In conclusion, reduced PFC, but not amygdala, gray matter volume is associated with social cognitive deficits in schizophrenia. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.

Computational study of noise in a large signal transduction network.

PubMed

Intosalmi, Jukka; Manninen, Tiina; Ruohonen, Keijo; Linne, Marja-Leena

2011-06-21

Biochemical systems are inherently noisy due to the discrete reaction events that occur in a random manner. Although noise is often perceived as a disturbing factor, the system might actually benefit from it. In order to understand the role of noise better, its quality must be studied in a quantitative manner. Computational analysis and modeling play an essential role in this demanding endeavor. We implemented a large nonlinear signal transduction network combining protein kinase C, mitogen-activated protein kinase, phospholipase A2, and β isoform of phospholipase C networks. We simulated the network in 300 different cellular volumes using the exact Gillespie stochastic simulation algorithm and analyzed the results in both the time and frequency domain. In order to perform simulations in a reasonable time, we used modern parallel computing techniques. The analysis revealed that time and frequency domain characteristics depend on the system volume. The simulation results also indicated that there are several kinds of noise processes in the network, all of them representing different kinds of low-frequency fluctuations. In the simulations, the power of noise decreased on all frequencies when the system volume was increased. We concluded that basic frequency domain techniques can be applied to the analysis of simulation results produced by the Gillespie stochastic simulation algorithm. This approach is suited not only to the study of fluctuations but also to the study of pure noise processes. Noise seems to have an important role in biochemical systems and its properties can be numerically studied by simulating the reacting system in different cellular volumes. Parallel computing techniques make it possible to run massive simulations in hundreds of volumes and, as a result, accurate statistics can be obtained from computational studies. © 2011 Intosalmi et al; licensee BioMed Central Ltd.

Stormbow: A Cloud-Based Tool for Reads Mapping and Expression Quantification in Large-Scale RNA-Seq Studies

PubMed Central

Zhao, Shanrong; Prenger, Kurt; Smith, Lance

2013-01-01

RNA-Seq is becoming a promising replacement to microarrays in transcriptome profiling and differential gene expression study. Technical improvements have decreased sequencing costs and, as a result, the size and number of RNA-Seq datasets have increased rapidly. However, the increasing volume of data from large-scale RNA-Seq studies poses a practical challenge for data analysis in a local environment. To meet this challenge, we developed Stormbow, a cloud-based software package, to process large volumes of RNA-Seq data in parallel. The performance of Stormbow has been tested by practically applying it to analyse 178 RNA-Seq samples in the cloud. In our test, it took 6 to 8 hours to process an RNA-Seq sample with 100 million reads, and the average cost was $3.50 per sample. Utilizing Amazon Web Services as the infrastructure for Stormbow allows us to easily scale up to handle large datasets with on-demand computational resources. Stormbow is a scalable, cost effective, and open-source based tool for large-scale RNA-Seq data analysis. Stormbow can be freely downloaded and can be used out of box to process Illumina RNA-Seq datasets. PMID:25937948

Numerical Simulation of the Working Process in the Twin Screw Vacuum Pump

NASA Astrophysics Data System (ADS)

Lu, Yang; Fu, Yu; Guo, Bei; Fu, Lijuan; Zhang, Qingqing; Chen, Xiaole

2017-08-01

Twin screw vacuum pumps inherit the advantages of screw machinery, such as high reliability, stable medium conveying, small vibration, simple and compact structures, convenient operation, etc, which have been widely used in petrochemical and air industry. On the basis of previous studies, this study analyzed the geometric features of variable pitch of the twin screw vacuum pump such as the sealing line, the meshing line and the volume between teeth. The mathematical model of numerical simulation of the twin screw vacuum pump was established. The leakage paths of the working volume including the sealing line and the addendum arc were comprehensively considered. The corresponding simplified geometric model of leakage flow was built up for different leak paths and the flow coefficients were calculated. The flow coefficient value range of different leak paths was given. The results showed that the flow coefficient of different leak paths can be taken as constant value for the studied geometry. The analysis of recorded indicator diagrams showed that the increasing rotational speed can dramatically decrease the exhaust pressure and the lower rotational speed can lead to over-compression. The pressure of the isentropic process which was affected by leakage was higher than the theoretical process.

Stormbow: A Cloud-Based Tool for Reads Mapping and Expression Quantification in Large-Scale RNA-Seq Studies.

PubMed

Zhao, Shanrong; Prenger, Kurt; Smith, Lance

2013-01-01

RNA-Seq is becoming a promising replacement to microarrays in transcriptome profiling and differential gene expression study. Technical improvements have decreased sequencing costs and, as a result, the size and number of RNA-Seq datasets have increased rapidly. However, the increasing volume of data from large-scale RNA-Seq studies poses a practical challenge for data analysis in a local environment. To meet this challenge, we developed Stormbow, a cloud-based software package, to process large volumes of RNA-Seq data in parallel. The performance of Stormbow has been tested by practically applying it to analyse 178 RNA-Seq samples in the cloud. In our test, it took 6 to 8 hours to process an RNA-Seq sample with 100 million reads, and the average cost was $3.50 per sample. Utilizing Amazon Web Services as the infrastructure for Stormbow allows us to easily scale up to handle large datasets with on-demand computational resources. Stormbow is a scalable, cost effective, and open-source based tool for large-scale RNA-Seq data analysis. Stormbow can be freely downloaded and can be used out of box to process Illumina RNA-Seq datasets.

Blood Volume: Importance and Adaptations to Exercise Training, Environmental Stresses and Trauma/Sickness

NASA Technical Reports Server (NTRS)

Sawka, Michael N.; Convertino, Victor A.; Eichner, E. Randy; Schnieder, Suzanne M.; Young, Andrew J.

2000-01-01

This paper reviews the influence of several perturbations (physical exercise, heat stress, terrestrial altitude, microgravity, and trauma/sickness) on adaptations of blood volume (BV), erythrocyte volume (EV), and plasma volume (PV). Exercise training can induced BV expansion; PV expansion usually occurs immediately, but EV expansion takes weeks. EV and PV expansion contribute to aerobic power improvements associated with exercise training. Repeated heat exposure induces PV expansion but does not alter EV. PV expansion does not improve thermoregulation, but EV expansion improves thermoregulation during exercise in the heat. Dehydration decreases PV (and increases plasma tonicity) which elevates heat strain and reduces exercise performance. High altitude exposure causes rapid (hours) plasma loss. During initial weeks at altitude, EV is unaffected, but a gradual expansion occurs with extended acclimatization. BV adjustments contribute, but are not key, to altitude acclimatization. Microgravity decreases PV and EV which contribute to orthostatic intolerance and decreased exercise capacity in astronauts. PV decreases may result from lower set points for total body water and central venous pressure, which EV decrease bay result form increased erythrocyte destruction. Trauma, renal disease, and chronic diseases cause anemia from hemorrhage and immune activation, which suppressions erythropoiesis. The re-establishment of EV is associated with healing, improved life quality, and exercise capabilities for these injured/sick persons.

The Role of Blood Osmolality and Volume in Regulating Vasopressin Secretion in the Rat

PubMed Central

Dunn, Fredrick L.; Brennan, Thomas J.; Nelson, Averial E.; Robertson, Gary L.

1973-01-01

A sensitive and specific radioimmunoassay for plasma arginine vasopressin (AVP) has been used to study the effects of blood osmolality and volume in regulating AVP secretion in unanesthetized rats. Under basal conditions, plasma AVP and osmolality were relatively constant, averaging 2.3±0.9 (SD) pg/ml and 294±1.4 mosmol/kg, respectively. Fluid restriction, which increased osmolality and decreased volume, resulted in a progressive rise in plasma AVP to about 10 times basal levels after 96 h. A 2-3-fold increase in plasma AVP occurred as early as 12 h, when osmolality and volume had each changed by less than 2%. Intraperitoneal injections of hypertonic saline, which had no effect on blood volume, also produced a rise in plasma AVP that was linearly correlated with the rise in osmolality (r > 0.9) and quantitatively similar to that found during fluid restriction (plasma AVP increased 2-4-fold with each 1% increase in osmolality). Intraperitoneal injection of polyethylene glycol, which decreased blood volume without altering osmolality, also increased plasma AVP but this response followed an exponential pattern and did not become significant until volume had decreased by 8% or more. At these levels of hypovolemia, the osmoregulatory system continued to function but showed a lower threshold and increase sensitivity to osmotic stimulation. We conclude that AVP secretion is regulated principally by blood osmolality but that the responsiveness of this mechanism may be significantly altered by modest changes in blood volume. PMID:4750450

First experiences with model based iterative reconstructions influence on quantitative plaque volume and intensity measurements in coronary computed tomography angiography.

PubMed

Precht, H; Kitslaar, P H; Broersen, A; Gerke, O; Dijkstra, J; Thygesen, J; Egstrup, K; Lambrechtsen, J

2017-02-01

Investigate the influence of adaptive statistical iterative reconstruction (ASIR) and the model-based IR (Veo) reconstruction algorithm in coronary computed tomography angiography (CCTA) images on quantitative measurements in coronary arteries for plaque volumes and intensities. Three patients had three independent dose reduced CCTA performed and reconstructed with 30% ASIR (CTDI vol at 6.7 mGy), 60% ASIR (CTDI vol 4.3 mGy) and Veo (CTDI vol at 1.9 mGy). Coronary plaque analysis was performed for each measured CCTA volumes, plaque burden and intensities. Plaque volume and plaque burden show a decreasing tendency from ASIR to Veo as median volume for ASIR is 314 mm 3 and 337 mm 3 -252 mm 3 for Veo and plaque burden is 42% and 44% for ASIR to 39% for Veo. The lumen and vessel volume decrease slightly from 30% ASIR to 60% ASIR with 498 mm 3 -391 mm 3 for lumen volume and vessel volume from 939 mm 3 to 830 mm 3 . The intensities did not change overall between the different reconstructions for either lumen or plaque. We found a tendency of decreasing plaque volumes and plaque burden but no change in intensities with the use of low dose Veo CCTA (1.9 mGy) compared to dose reduced ASIR CCTA (6.7 mGy & 4.3 mGy), although more studies are warranted. Copyright © 2016 The College of Radiographers. Published by Elsevier Ltd. All rights reserved.

Differential regional gray matter volumes in patients with on-line game addiction and professional gamers.

PubMed

Han, Doug Hyun; Lyoo, In Kyoon; Renshaw, Perry F

2012-04-01

Patients with on-line game addiction (POGA) and professional video game players play video games for extended periods of time, but experience very different consequences for their on-line game play. Brain regions consisting of anterior cingulate, thalamus and occpito-temporal areas may increase the likelihood of becoming a pro-gamer or POGA. Twenty POGA, seventeen pro-gamers, and eighteen healthy comparison subjects (HC) were recruited. All magnetic resonance imaging (MRI) was performed on a 1.5 Tesla Espree MRI scanner (SIEMENS, Erlangen, Germany). Voxel-wise comparisons of gray matter volume were performed between the groups using the two-sample t-test with statistical parametric mapping (SPM5). Compared to HC, the POGA group showed increased impulsiveness and perseverative errors, and volume in left thalamus gray matter, but decreased gray matter volume in both inferior temporal gyri, right middle occipital gyrus, and left inferior occipital gyrus, compared with HC. Pro-gamers showed increased gray matter volume in left cingulate gyrus, but decreased gray matter volume in left middle occipital gyrus and right inferior temporal gyrus compared with HC. Additionally, the pro-gamer group showed increased gray matter volume in left cingulate gyrus and decreased left thalamus gray matter volume compared with the POGA group. The current study suggests that increased gray matter volumes of the left cingulate gyrus in pro-gamers and of the left thalamus in POGA may contribute to the different clinical characteristics of pro-gamers and POGA. Copyright © 2012 Elsevier Ltd. All rights reserved.

Measurable Supratentorial White Matter Volume Changes in Patients with Diffuse Intrinsic Pontine Glioma Treated with an Anti-Vascular Endothelial Growth Factor Agent, Steroids, and Radiation.

PubMed

Svolos, P; Reddick, W E; Edwards, A; Sykes, A; Li, Y; Glass, J O; Patay, Z

2017-06-01

Assessing the response to treatment in infiltrative brain tumors by using lesion volume-based response criteria is challenging. We hypothesized that in such tumors, volume measurements alone may not accurately capture changes in actual tumor burden during treatment. We longitudinally evaluated volume changes in both normal-appearing supratentorial white matter and the brain stem lesions in patients treated for diffuse intrinsic pontine glioma to determine to what extent adjuvant systemic therapies may skew the accuracy of tumor response assessments based on volumetric analysis. The anatomic MR imaging and diffusion tensor imaging data of 26 patients with diffuse intrinsic pontine glioma were retrospectively analyzed. Treatment included conformal radiation therapy in conjunction with vandetanib and dexamethasone. Volumetric and diffusion data were analyzed with time, and differences between time points were evaluated statistically. Normalized brain stem lesion volume decreased during combined treatment (slope = -0.222, P < .001) and increased shortly after completion of radiation therapy (slope = 0.422, P < .001). Supratentorial white matter volume steadily and significantly decreased with time (slope = -0.057, P < .001). Longitudinal changes in brain stem lesion volume are robust; less pronounced but measurable changes occur in the supratentorial white matter. Volume changes in nonirradiated supratentorial white matter during the disease course reflect the effects of systemic medication on the water homeostasis of normal parenchyma. Our data suggest that adjuvant nontumor-targeted therapies may have a more substantial effect on lesion volume changes than previously thought; hence, an apparent volume decrease in infiltrative tumors receiving combined therapies may lead to overestimation of the actual response and tumor control. © 2017 by American Journal of Neuroradiology.

The measurement of peripheral blood volume reactions to tilt test by the electrical impedance technique after exercise in athletes

NASA Astrophysics Data System (ADS)

Melnikov, A. A.; Popov, S. G.; Nikolaev, D. V.; Vikulov, A. D.

2013-04-01

We have investigated the distribution of peripheral blood volumes in different regions of the body in response to the tilt-test in endurance trained athletes after aerobic exercise. Distribution of peripheral blood volumes (ml/beat) simultaneously in six regions of the body (two legs, two hands, abdomen, neck and ECG) was assessed in response to the tilt-test using the impedance method (the impedance change rate (dZ/dT). Before and after exercise session cardiac stroke (CSV) and blood volumes in legs, arms and neck were higher in athletes both in lying and standing positions. Before exercise the increase of heart rate and the decrease of a neck blood volume in response to tilting was lower (p <0.05) but the decrease of leg blood volumes was higher (p<0.001) in athletes. The reactions in arms and abdomen blood volumes were similar. Also, the neck blood volumes as percentage of CSV (%/CSV) did not change in the control but increased in athletes (p <0.05) in response to the tilt test. After (10 min recovery) the aerobic bicycle exercise (mean HR = 156±8 beat/min, duration 30 min) blood volumes in neck and arms in response to the tilting were reduced equally, but abdomen (p<0.05) and leg blood volumes (p <0.001) were lowered more significantly in athletes. The neck blood flow (%/CSV) did not change in athletes but decreased in control (p<0.01), which was offset by higher tachycardia in response to tilt-test in controls after exercise. The data demonstrate greater orthostatic tolerance in athletes both before and after exercise during fatigue which is due to effective distribution of blood flows aimed at maintaining cerebral blood flow.

Dentate gyrus-cornu ammonis (CA) 4 volume is decreased and associated with depressive episodes and lipid peroxidation in bipolar II disorder: Longitudinal and cross-sectional analyses.

PubMed

Elvsåshagen, Torbjørn; Zuzarte, Pedro; Westlye, Lars T; Bøen, Erlend; Josefsen, Dag; Boye, Birgitte; Hol, Per K; Malt, Ulrik F; Young, L Trevor; Andreazza, Ana C

2016-12-01

Reduced dentate gyrus volume and increased oxidative stress have emerged as potential pathophysiological mechanisms in bipolar disorder. However, the relationship between dentate gyrus volume and peripheral oxidative stress markers remains unknown. Here, we examined dentate gyrus-cornu ammonis (CA) 4 volume longitudinally in patients with bipolar II disorder (BD-II) and healthy controls and investigated whether BD-II is associated with elevated peripheral levels of oxidative stress. We acquired high-resolution structural 3T-magnetic resonance imaging (MRI) images and quantified hippocampal subfield volumes using an automated segmentation algorithm in individuals with BD-II (n=29) and controls (n=33). The participants were scanned twice, at study inclusion and on average 2.4 years later. In addition, we measured peripheral levels of two lipid peroxidation markers (4-hydroxy-2-nonenal [4-HNE] and lipid hydroperoxides [LPH]). First, we demonstrated that the automated hippocampal subfield segmentation technique employed in this work reliably measured dentate gyrus-CA4 volume. Second, we found a decreased left dentate gyrus-CA4 volume in patients and that a larger number of depressive episodes between T1 and T2 predicted greater volume decline. Finally, we showed that 4-HNE was elevated in BD-II and that 4-HNE was negatively associated with left and right dentate gyrus-CA4 volumes in patients. These results are consistent with a role for the dentate gyrus in the pathophysiology of bipolar disorder and suggest that depressive episodes and elevated oxidative stress might contribute to hippocampal volume decreases. In addition, these findings provide further support for the hypothesis that peripheral lipid peroxidation markers may reflect brain alterations in bipolar disorders. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of C and Si on strain aging of strain-based API X60 pipeline steels

NASA Astrophysics Data System (ADS)

Sung, Hyo Kyung; Lee, Dong Ho; Lee, Sunghak; Lee, Byeong-Joo; Hong, Seung-Pyo; Kim, Young-Woon; Yoo, Jang Yong; Hwang, Byoungchul; Shin, Sang Yong

2017-05-01

Four types of strain-based API X60 pipeline steels were fabricated by varying the C and Si contents, and the effects of C and Si on strain aging were investigated. The 0.05 wt% C steels consisted mainly of polygonal ferrite (PF), whereas the 0.08 wt% C steels consisted of acicular ferrite (AF). The volume fraction of AF increased with increasing C content because C is an austenite stabilizer element. The volume fractions of bainitic ferrite (BF) of the 0.15 wt% Si steels were higher than those of the 0.25 wt% Si steels, whereas the volume fractions of the secondary phases were lower. From the tensile properties before and after the aging process of the strainbased API X60 pipeline steels, the yield strength increased and the uniform and total elongation decreased, which is the strain aging effect. The strain aging effect in the strain-based API X60 pipeline steels was minimized when the volume fraction of AF was increased and secondary phases were distributed uniformly. On the other hand, an excessively high C content formed fine precipitates, and the strain aging effect occurred because of the interactions among dislocations and fine precipitates.

Voxel-based morphometry study of the insular cortex in bipolar depression.

PubMed

Tang, Li-Rong; Liu, Chun-Hong; Jing, Bin; Ma, Xin; Li, Hai-Yun; Zhang, Yu; Li, Feng; Wang, Yu-Ping; Yang, Zhi; Wang, Chuan-Yue

2014-11-30

Bipolar depression (BD) is a common psychiatric illness characterized by deficits in emotional and cognitive processing. Abnormalities in the subregions of the insula are common findings in neuroanatomical studies of patients with bipolar disorder. However, the specific relationships between morphometric changes in specific insular subregions and the pathogenesis of BD are not clear. In this study, structural magnetic resonance imaging (MRI) was used to investigate gray matter volume abnormalities in the insular subregion in 27 patients with BD and in 27 age and sex-matched controls. Using DARTEL (diffeomorphic anatomical registration through exponentiated lie algebra) for voxel-based morphometry (VBM), we examined changes in regional gray matter volumes of the insula in patients with BD. As compared with healthy controls, the BD patients showed decreased gray matter volumes in the right posterior insula and left ventral anterior insula and increased gray matter volumes in the left dorsal anterior insula. Consistent with the emerging theory of insular interference as a contributor to emotional-cognitive dysregulation, the current findings suggest that the insular cortex may be involved in the neural substrates of BD. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

A fully automated non-external marker 4D-CT sorting algorithm using a serial cine scanning protocol.

PubMed

Carnes, Greg; Gaede, Stewart; Yu, Edward; Van Dyk, Jake; Battista, Jerry; Lee, Ting-Yim

2009-04-07

Current 4D-CT methods require external marker data to retrospectively sort image data and generate CT volumes. In this work we develop an automated 4D-CT sorting algorithm that performs without the aid of data collected from an external respiratory surrogate. The sorting algorithm requires an overlapping cine scan protocol. The overlapping protocol provides a spatial link between couch positions. Beginning with a starting scan position, images from the adjacent scan position (which spatial match the starting scan position) are selected by maximizing the normalized cross correlation (NCC) of the images at the overlapping slice position. The process was continued by 'daisy chaining' all couch positions using the selected images until an entire 3D volume was produced. The algorithm produced 16 phase volumes to complete a 4D-CT dataset. Additional 4D-CT datasets were also produced using external marker amplitude and phase angle sorting methods. The image quality of the volumes produced by the different methods was quantified by calculating the mean difference of the sorted overlapping slices from adjacent couch positions. The NCC sorted images showed a significant decrease in the mean difference (p < 0.01) for the five patients.

Effect of martensitic transformation on springback behavior of 304L austenitic stainless steel

NASA Astrophysics Data System (ADS)

Fathi, H.; Mohammadian Semnani, H. R.; Emadoddin, E.; Sadeghi, B. Mohammad

2017-09-01

The present paper studies the effect of martensitic transformation on the springback behavior of 304L austenitic stainless steel. Martensite volume fraction was determined at the bent portion under various strain rates after bending test. Martensitic transformation has a significant effect on the springback behavior of this material. The findings of this study indicated that the amount of springback was reduced under a situation of low strain rate, while a higher amount of springback was obtained with a higher strain rate. The reason for this phenomenon is that higher work hardening occurs during the forming process with the low strain rate due to the higher martensite volume fraction, therefore the formability of the sheet is enhanced and it leads to a decreased amount of springback after the bending test. Dependency of the springback on the martensite volume fraction and strain rate was expressed as formulas from the results of the experimental tests and simulation method. Bending tests were simulated using LS-DYNA software and utilizing MAT_TRIP to determine the martensite volume fraction and strain under various strain rates. Experimental result reveals good agreement with the simulation method.

Does recyclable separation reduce the cost of municipal waste management in Japan?

PubMed

Chifari, Rosaria; Lo Piano, Samuele; Matsumoto, Shigeru; Tasaki, Tomohiro

2017-02-01

Municipal solid waste (MSW) management is a system involving multiple sub-systems that typically require demanding inputs, materials and resources to properly process generated waste throughput. For this reason, MSW management is generally one of the most expensive services provided by municipalities. In this paper, we analyze the Japanese MSW management system and estimate the cost elasticity with respect to the waste volumes at three treatment stages: collection, processing, and disposal. Although we observe economies of scale at all three stages, the collection cost is less elastic than the disposal cost. We also examine whether source separation at home affects the cost of MSW management. The empirical results show that the separate collection of the recyclable fraction leads to reduced processing costs at intermediate treatment facilities, but does not change the overall waste management cost. Our analysis also reveals that the cost of waste management systems decreases when the service is provided by private companies through a public tender. The cost decreases even more when the service is performed under the coordination of adjacent municipalities. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hypnosis for exercise-induced asthma.

PubMed

Ben-Zvi, Z; Spohn, W A; Young, S H; Kattan, M

1982-04-01

Hypnosis has been used for many years in the treatment of asthma, but studies of its usefulness have been controversial. We assessed the efficacy of hypnosis in attenuating exercise-induced asthma (EIA) in 10 stable asthmatics. The subjects ran on a treadmill while mouth breathing for 6 min on 5 different days. Pulmonary mechanics were measured before and after each challenge. Two control exercise challenges resulted in a reproducible decrease in forced expiratory volume in one second (FEV1). On 2 other days, saline or cromolyn by nebulization was given in a double-blind manner with the suggestion that these agents would prevent EIA. Hypnosis prior to exercise resulted in a 15.9% decrease in FEV1 compared with a 31.8% decrease on the control days (p less than 0.001). Pretreatment with cromolyn resulted in a 7.6% decrease in FEV1. We conclude that hypnosis can alter the magnitude of a pathophysiologic process, namely, the bronchospasm after exercise in patients with asthma.

Spider phobia is associated with decreased left amygdala volume: a cross-sectional study

PubMed Central

2013-01-01

Background Evidence from animal and human studies imply the amygdala as the most critical structure involved in processing of fear-relevant stimuli. In phobias, the amygdala seems to play a crucial role in the pathogenesis and maintenance of the disorder. However, the neuropathology of specific phobias remains poorly understood. In the present study, we investigated whether patients with spider phobia show altered amygdala volumes as compared to healthy control subjects. Methods Twenty female patients with spider phobia and twenty age-matched healthy female controls underwent magnetic resonance imaging to investigate amygdala volumes. The amygdalae were segmented using an automatic, model-based segmentation tool (FSL FIRST). Differences in amygdala volume were investigated by multivariate analysis of covariance with group as between-subject factor and left and right amygdala as dependent factors. The relation between amygdala volume and clinical features such as symptom severity, disgust sensitivity, trait anxiety and duration of illness was investigated by Spearman correlation analysis. Results Spider phobic patients showed significantly smaller left amygdala volume than healthy controls. No significant difference in right amygdala volume was detected. Furthermore, the diminished amygdala size in patients was related to higher symptom severity, but not to higher disgust sensitivity or trait anxiety and was independent of age. Conclusions In summary, the results reveal a relation between higher symptom severity and smaller left amygdala volume in patients with spider phobia. This relation was independent of other potential confounders such as the disgust sensitivity or trait anxiety. The findings suggest that greater spider phobic fear is associated with smaller left amygdala. However, the smaller left amygdala volume may either stand for a higher vulnerability to develop a phobic disorder or emerge as a consequence of the disorder. PMID:23442196

Functionally Graded Aluminum Foam Fabricated by Friction Powder Sintering Process with Traversing Tool

NASA Astrophysics Data System (ADS)

Hangai, Yoshihiko; Morita, Tomoaki; Koyama, Shinji; Kuwazuru, Osamu; Yoshikawa, Nobuhiro

2016-09-01

Functionally graded aluminum foam (FG Al foam) is a new class of Al foam in which the pore structure varies over the foam, resulting in corresponding variations in the mechanical properties of the foam. In this study, FG Al foam plates were fabricated by a friction powder sintering (FPS) process with a traversing tool that is based on a previously developed sintering and dissolution process. The variation of the mechanical properties was realized by setting the volume fraction φ of NaCl in the mixture to 60, 70, and 80%. Long FG Al foam plates were fabricated with a length equal to the tool traversing length with φ varying in the tool traversing direction. From x-ray computed tomography observation, it was shown that the density of the Al foam decreased with increasing φ. In contrast, almost uniform pore structures were obtained in each area. According to the results of compression tests on each area, the plateau stress and energy absorption tended to decrease with increasing φ. Therefore, it was shown that FG Al foam plates with varying mechanical properties can be fabricated by the FPS process with the traversing tool.

A classification scheme for the morphology of lava flow fields

NASA Technical Reports Server (NTRS)

Wilson, L.; Pinkerton, H.; Head, James W.; Roberts, K. Magee

1993-01-01

Analysis of the processes controlling the advance of lava flows shows that, if no other factors intervene, thermal constraints will act to limit the maximum length of a flow being fed at a given volume or mass effusion rate from a vent. These constraints can be characterized through the Gratz number, which takes on a large value at the vent and decreases down flow. Early application of this principle showed that, despite the many subtleties of modes of heat loss from flows, motion apparently ceases when the Gratz number has decreased to a value close to 300. Recent analyses of flow units from the 1983-86 Pu'u 'O'o eruption of Kilauea and of other, more silicic lava flow units confirm this finding.

Titanium 󈨠: Science and Technology. Proceedings of a Symposium Sponsored by the Titanium Committee of the Minerals, Metals and Materials Structural Metals Division Held at the World Titanium Conference (7th) in San Diego, California on June 29-July 2, 1992. Volume 2

DTIC Science & Technology

1993-01-01

Hong, and B.J. Marquardt Microstructure, Tensile Ductility, and Fracture Toughness of Ti-25AI- 1ONb-3V- 1M o ...tend to form with a decreasing Al or an increasing Cr concentration 1211. In Ti-48.4A1- O .6fo (at%), thermomechanical processing has been reported to...and all annealed at 9001C. It can be seen that the decrease in microhardness 500 -0-- 15% -zk-30 0 /a > 400 --- 0- 40%/ o S 300 > •As-grown 200. I 1 10

Optimization of the Ethanol Recycling Reflux Extraction Process for Saponins Using a Design Space Approach

PubMed Central

Gong, Xingchu; Zhang, Ying; Pan, Jianyang; Qu, Haibin

2014-01-01

A solvent recycling reflux extraction process for Panax notoginseng was optimized using a design space approach to improve the batch-to-batch consistency of the extract. Saponin yields, total saponin purity, and pigment yield were defined as the process critical quality attributes (CQAs). Ethanol content, extraction time, and the ratio of the recycling ethanol flow rate and initial solvent volume in the extraction tank (RES) were identified as the critical process parameters (CPPs) via quantitative risk assessment. Box-Behnken design experiments were performed. Quadratic models between CPPs and process CQAs were developed, with determination coefficients higher than 0.88. As the ethanol concentration decreases, saponin yields first increase and then decrease. A longer extraction time leads to higher yields of the ginsenosides Rb1 and Rd. The total saponin purity increases as the ethanol concentration increases. The pigment yield increases as the ethanol concentration decreases or extraction time increases. The design space was calculated using a Monte-Carlo simulation method with an acceptable probability of 0.90. Normal operation ranges to attain process CQA criteria with a probability of more than 0.914 are recommended as follows: ethanol content of 79–82%, extraction time of 6.1–7.1 h, and RES of 0.039–0.040 min−1. Most of the results of the verification experiments agreed well with the predictions. The verification experiment results showed that the selection of proper operating ethanol content, extraction time, and RES within the design space can ensure that the CQA criteria are met. PMID:25470598

Clonidine reduces diarrhea and sodium loss in patients with proximal jejunostomy: a controlled study.

PubMed

Buchman, Alan L; Fryer, Jon; Wallin, Anita; Ahn, Chul W; Polensky, Sharon; Zaremba, Karen

2006-01-01

Patients with short bowel syndrome have significant fluid losses. This represents a significant management problem, especially in patients with minimal residual intestine. We determined whether clonidine, an alpha2-adrenergic agonist, is effective in decreasing fecal water and sodium (Na) losses in patients with proximal jejunostomy. Eight parenteral nutrition (PN)-dependent subjects (3 men, 5 women), aged 49.9+/-10.2 years, with a residual small bowel length of 71.8+/-152.0 cm that ended in a jejunostomy, were studied. Subjects were admitted to the North-western General Clinical Research Center (GCRC) for a 2-day equilibrium period while receiving a self-selected 100 g fat diet with protein 1.5 g/kg/d and 30 kcal/kg/d and 1 L/d of oral rehydration solution. A D-xylose test was performed after an overnight fast. On days 3-5, all stool and urine were collected for volume, weight, fat, nitrogen, energy, sodium, magnesium, potassium, and calcium. Meals were provided in duplicate and the equivalent portions consumed by each patient were analyzed for fluid volume, fat, nitrogen, energy, sodium, magnesium, calcium, and potassium in order to calculate nutrient balances. At the conclusion of the stool and urine collections (day 6), a clonidine (0.3 mg) patch was applied to the shoulder. Subjects were restudied after 1 week. Daily fecal volume and weight were 4.514+/-1.769 L/d and 4394+/-1727 g/d, respectively, at baseline. Five subjects were net "secretors" in that excreted fecal volume exceeded oral intake. Fecal volume decreased by 427+/-562 mL/d (8.9%, p=.07). Fecal weight decreased by 438+/-527 g/d (9.4%, p=.05). Urine volume correspondingly increased by 747+/-1934 mL (18.9%, p=not significant [NS]). The increase in urine output was weakly and negatively correlated with the decrease in fecal volume and weight (r=-0.37 and -0.41, respectively, p=NS). Oral fluid intake decreased slightly from 3.328+/-1.246 L/d baseline to 3.203+/-1.119 L/d with clonidine therapy (-3.8%, p=NS). Fecal Na loss was significantly decreased from baseline (887+/-996 mg/d, 11.2+/-12.3%; p=.036). This was not related to decreased oral Na intake, which actually increased from baseline (3.799+/-2.271 g/d) to 3.933+/-1.314 g/d after clonidine therapy (p=NS). No patient developed hypotension. Our results show the transdermal administration of clonidine is associated with a modest but clinically significant decrease in fecal output in patients with short bowel syndrome and high-output proximal jejunostomy that require chronic parenteral fluid infusion. This is accompanied by decreased fecal Na loss.

Predictive value of ridge dimensions on autologous bone graft resorption in staged maxillary sinus augmentation surgery using Cone-Beam CT.

PubMed

Klijn, R J; van den Beucken, J J J P; Bronkhorst, E M; Berge, S J; Meijer, G J; Jansen, J A

2012-04-01

No studies are available that provide predictive parameters regarding the expected amount of resorption after maxillary sinus augmentation surgery using autologous bone grafts. Therefore, the aim of this study was to determine parameters influencing the outcome of the bone graft resorption process. In 20 patients, three-dimensional analysis of alveolar ridge dimensions and bone graft volume change in the atrophic posterior maxilla was performed by Cone-Beam Computerized Tomography imaging. Ridge dimensions were assessed before maxillary sinus augmentation surgery. Bone graft volumes were compared after maxillary sinus floor augmentation surgery and a graft healing interval of several months. To analyze the relation between bone volume changes with the independent variables, patients' gender, age, alveolar crest height and width, and graft healing time interval, a multi-level extension of linear regression was applied. A residual bone height of 6.0 mm (SD = 3.6 mm) and 6.2 mm (SD = 3.6 mm) was found at the left and right sides, respectively. Moreover, alveolar bone widths of 6.5 mm (SD = 2.2 mm) and 7.0 mm (SD = 2.3 mm) at the premolars, and 8.8 mm (SD = 2.2 mm) and 8.9 mm (SD = 2.5 mm) at the molars regions were found at the left and right site, respectively. Bone graft volume decreased by 25.0% (SD = 21.0%) after 4.7 months (SD = 2.7, median = 4.0 months) of healing time. The variables "age" (P = 0.009) and mean alveolar crest "bone height" (P = 0.043), showed a significant influence on bone graft resorption. A decrease of 1.0% (SE = 0.3%) of bone graft resorption was found for each year the patient grew older, and an increase in bone graft resorption of 1.8% (SE = 0.8%) was found for each mm of original bone height before sinus floor augmentation. Graft resorption occurs when using autologous bone grafts for maxillary sinus augmentation. Alveolar crest bone height and patient age have a significant effect on graft resorption, with increased resorption for higher alveolar crest bone height and decreased resorption for older patients. Consequently, patient characteristics that affect the process of bone graft resorption should be given full consideration, when performing sinus augmentation surgery. © 2011 John Wiley & Sons A/S.

Dielectric spectroscopy of polymer-metal composites across the percolation threshold

NASA Astrophysics Data System (ADS)

Panda, Maheswar; Srinivas, V.; Thakur, A. K.

2014-11-01

Polymer (polar/nonpolar)/metal composites (PMC) were prepared under different process conditions. In polar PMC, dipolar relaxation plays a predominant role below percolation threshold (fc) and anomalous low frequency dispersion (ALFD) becomes dominant above fc while ALFD is the only likely possibility for nonpolar PMC above fc. The magnitude of relaxation exponents "m", "p" and "n", evaluated from the experimental results using Jonscher's universal dielectric response (JUDR) laws, falls within the universal limit [0, 1] with additional feature of strong dependence on volume fraction of conductor (fcon). The decrease in the relaxation exponent "m" with an increase of fcon is directly linked with decrease in the number of dipoles of the polymer in the composite and is accompanied by a distribution of relaxation time due to increased heterogeneity of the system. The magnitude of the relaxation exponent "n" decreases at fc, due to the prevalence of Maxwell-Wagner-Sillar polarization contributed by uncorrelated electrons.

Temporal variation of dielectric properties of preserved blood.

PubMed

Hayashi, Yoshihito; Oshige, Ikuya; Katsumoto, Yoichi; Omori, Shinji; Yasuda, Akio; Asami, Koji

2008-01-07

Rabbit blood was preserved at 277 K in Alsever's solution for 37 days, and its dielectric permittivity was monitored in a frequency range from 0.05 to 110 MHz throughout the period. The relaxation time and Cole-Cole parameter of the interfacial polarization process for erythrocytes remained nearly constant during the first 20 days and then started to increase and decrease, respectively. On the other hand, the relaxation strength and the cell volume fraction continued to decrease for 37 days, but the decrease rates of both changed discontinuously on about the 20th day. Microscope observation showed that approximately 90% of the erythrocytes were spinous echinocytes at the beginning of preservation and started to be transformed into microspherocytes around the 20th day. Therefore, dielectric spectroscopy is a sensitive tool to monitor the deterioration of preserved blood accompanied by morphological transition of erythrocytes through the temporal variation of their dielectric properties.

SU-F-T-378: Evaluation of Dose-Volume Variability and Parameters Between Prostate IMRT and VMAT Plans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chow, J; Jiang, R; Kiciak, A

2016-06-15

Purpose: This study compared the rectal dose-volume consistency, equivalent uniform dose (EUD) and normal tissue complication probability (NTCP) in prostate intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT). Methods: For forty prostate IMRT and fifty VMAT patients treated using the same dose prescription (78 Gy/39 fraction) and dose-volume criteria in inverse planning optimization, the rectal EUD and NTCP were calculated for each patient. The rectal dose-volume consistency, showing the variability of dose-volume histogram (DVH) among patients, was defined and calculated based on the deviation between the mean and corresponding rectal DVH. Results: From both the prostate IMRT andmore » VMAT plans, the rectal EUD and NTCP were found decreasing with the rectal volume. The decrease rates for the IMRT plans (EUD = 0.47 × 10{sup −3} Gy cm{sup −3} and NTCP = 3.94 × 10{sup −2} % cm{sup −3}) were higher than those for the VMAT (EUD = 0.28 × 10{sup −3} Gy cm{sup −3} and NTCP = 2.61 × 10{sup −2} % cm{sup −3}). In addition, the dependences of the rectal EUD and NTCP on the dose-volume consistency were found very similar between the prostate IMRT and VMAT plans. This shows that both delivery techniques have similar variations of the rectal EUD and NTCP on the dose-volume consistency. Conclusion: Dependences of the dose-volume consistency on the rectal EUD and NTCP were compared between the prostate IMRT and VMAT plans. It is concluded that both rectal EUD and NTCP decreased with an increase of the rectal volume. The variation rates of the rectal EUD and NTCP on the rectal volume were higher for the IMRT plans than VMAT. However, variations of the rectal dose-volume consistency on the rectal EUD and NTCP were found not significant for both delivery techniques.« less

Learning curve in transradial cardiac catheterization: procedure-related parameters stratified by operators' transradial volume.

PubMed

Kasasbeh, Ehab S; Parvez, Babar; Huang, Robert L; Hasselblad, Michele Marie; Glazer, Mark D; Salloum, Joseph G; Cleator, John H; Zhao, David X

2012-11-01

To determine whether radial artery access is associated with a reduction in fluoroscopy time, procedure time, and other procedural variables over a 27-month period during which the radial artery approach was incorporated in a single academic Medical Center. Although previous studies have demonstrated a relationship between increased volume and decreased procedural time, no studies have looked at the integration of radial access over time. Data were collected from consecutive patients who presented to the Vanderbilt University Medical Center cardiac catheterization laboratory from January 1, 2009 to April 1, 2011. Patients who underwent radial access diagnostic catheterization with and without percutaneous coronary intervention were included in this study. A total of 1112 diagnostic cardiac catheterizations through the radial access site were analyzed. High-volume, intermediate-volume, and low-volume operators were grouped based on the percentage of procedures performed through a radial approach. From 2009 to 2011, there was a significant decrease in fluoroscopy time in all operator groups for diagnostic catheterization (P=.035). The high-volume operator group had 1.88 and 3.66 minute reductions in fluoroscopy time compared to the intermediate- and low-volume operator groups, respectively (both P<.001). Likewise, the intermediate-volume operator group had a 1.77 minute improvement compared to the low-volume operator group, but this did not reach statistical significance (P=.102). The improvement in fluoroscopy time and other procedure-related parameters was seen after approximately 25 cases with further improvement after 75 cases. The incorporation of the radial access approach in the cardiac catheterization laboratory led to a decrease in fluoroscopy time for each operator and operator group over the last 3 years. Our data demonstrated that higher-volume radial operators have better procedure, room, and fluoroscopy times when compared to intermediate- and low-volume operators. However, lower-volume operators have a reduction in procedure-related parameters with increased radial cases. Number of procedures needed to become sufficient was demonstrated in the current study.

Thermal activation parameters of plastic flow reveal deformation mechanisms in the CrMnFeCoNi high-entropy alloy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laplanche, Guillaume; Bonneville, J.; Varvenne, C.

To reveal the operating mechanisms of plastic deformation in an FCC high-entropy alloy, the activation volumes in CrMnFeCoNi have been measured as a function of plastic strain and temperature between 77 K and 423 K using repeated load relaxation experiments. At the yield stress, σ y, the activation volume varies from ~60 b3 at 77 K to ~360 b 3 at 293 K and scales inversely with yield stress. With increasing plastic strain, the activation volume decreases and the trends follow the Cottrell-Stokes law, according to which the inverse activation volume should increase linearly with σ - σ y (Haasenmore » plot). This is consistent with the notion that hardening due to an increase in the density of forest dislocations is naturally associated with a decrease in the activation volume because the spacing between dislocations decreases. The values and trends in activation volume agree with theoretical predictions that treat the HEA as a high-concentration solid-solution-strengthened alloy. Lastly, these results demonstrate that this HEA deforms by the mechanisms typical of solute strengthening in FCC alloys, and thus indicate that the high compositional/structural complexity does not introduce any new intrinsic deformation mechanisms.« less

Thermal activation parameters of plastic flow reveal deformation mechanisms in the CrMnFeCoNi high-entropy alloy

DOE PAGES

Laplanche, Guillaume; Bonneville, J.; Varvenne, C.; ...

2017-10-06

To reveal the operating mechanisms of plastic deformation in an FCC high-entropy alloy, the activation volumes in CrMnFeCoNi have been measured as a function of plastic strain and temperature between 77 K and 423 K using repeated load relaxation experiments. At the yield stress, σ y, the activation volume varies from ~60 b3 at 77 K to ~360 b 3 at 293 K and scales inversely with yield stress. With increasing plastic strain, the activation volume decreases and the trends follow the Cottrell-Stokes law, according to which the inverse activation volume should increase linearly with σ - σ y (Haasenmore » plot). This is consistent with the notion that hardening due to an increase in the density of forest dislocations is naturally associated with a decrease in the activation volume because the spacing between dislocations decreases. The values and trends in activation volume agree with theoretical predictions that treat the HEA as a high-concentration solid-solution-strengthened alloy. Lastly, these results demonstrate that this HEA deforms by the mechanisms typical of solute strengthening in FCC alloys, and thus indicate that the high compositional/structural complexity does not introduce any new intrinsic deformation mechanisms.« less

MACULAR CHOROIDAL VOLUME CHANGES AFTER INTRAVITREAL BEVACIZUMAB FOR EXUDATIVE AGE-RELATED MACULAR DEGENERATION.

PubMed

Palkovits, Stefan; Seidel, Gerald; Pertl, Laura; Malle, Eva M; Hausberger, Silke; Makk, Johanna; Singer, Christoph; Osterholt, Julia; Herzog, Sereina A; Haas, Anton; Weger, Martin

2017-12-01

To evaluate the effect of intravitreal bevacizumab on the macular choroidal volume and the subfoveal choroidal thickness in treatment naïve eyes with exudative age-related macular degeneration. The macular choroidal volume and the subfoveal choroidal thickness were measured using enhanced depth imaging optical coherence tomography. After a screening examination, each patient received 3 monthly intravitreal injections of 1.25 mg bevacizumab. One month after the third injection was a final assessment. Forty-seven patients with a mean age of 80 ± 6.4 years were included. The macular choroidal volume decreased significantly from median 4.1 mm (interquartile range 3.4-5.9) to median 3.9 mm (interquartile range 3.1-5.6) between the baseline and final examination (difference -0.46 mm, 95% confidence interval: -0.57 to 0.35, P < 0.001). Similarly, subfoveal choroidal thickness had decreased from 157.0 μm (interquartile range 116.0-244.5) at baseline to 139.0 μm (interquartile range 102.5-212.0) at the final examination (P < 0.001). Both parameters macular choroidal volume at baseline and subfoveal choroidal thickness at baseline were not associated with the response to treatment. The macular choroidal volume and the subfoveal choroidal thickness decreased significantly after 3 monthly bevacizumab injections for exudative age-related macular degeneration.

The Regionalization of Lumbar Spine Procedures in New York State: A 10-Year Analysis.

PubMed

Jancuska, Jeffrey; Adrados, Murillo; Hutzler, Lorraine; Bosco, Joseph

2016-01-01

A retrospective review of an administrative database. The purpose of this study is to determine the current extent of regionalization by mapping lumbar spine procedures according to hospital and patient zip code, as well as examine the rate of growth of lumbar spine procedures performed at high-, medium-, and low-volume institutions in New York State. The association between hospital and spine surgeon volume and improved patient outcomes is well established. There is no study investigating the actual process of patient migration to high-volume hospitals. New York Statewide Planning and Research Cooperative System (SPARCS) administrative data were used to identify 228,695 lumbar spine surgery patients from 2005 to 2014. The data included the patients' zip code, hospital of operation, and year of discharge. The volume of lumbar spine surgery in New York State was mapped according to patient and hospital 3-digit zip code. New York State hospitals were categorized as low, medium, and high volume and descriptive statistics were used to determine trends in changes in hospital volume. Lumbar spine surgery recipients are widely distributed throughout the state. Procedures are regionalized on a select few metropolitan centers. The total number of procedures grew 2.5% over the entire 10-year-period. High-volume hospital caseload increased 50%, from 7253 procedures in 2005 to 10,915 procedures in 2014. The number of procedures at medium and low-volume hospitals decreased 30% and 13%, respectively. Despite any concerted effort aimed at moving orthopedic patients to high-volume hospitals, migration to high-volume centers occurred. Public interest in quality outcomes and cost, as well as financial incentives among medical centers to increase market share, potentially influence the migration of patients to high-volume centers. Further regionalization has the potential to exacerbate the current level of disparities among patient populations at low and high-volume hospitals. 3.

Analysis of water level variation of lakes and reservoirs in Xinjiang, China using ICESat laser altimetry data (2003–2009)

PubMed Central

Liu, Hongxing; Chen, Yaning; Shu, Song; Wu, Qiusheng; Wang, Shujie

2017-01-01

This study utilizes ICESat Release 33 GLA14 data to analyse water level variation of Xinjiang’s lakes and reservoirs from 2003 to 2009. By using Landsat images, lakes and reservoirs with area larger than 1 km2 are numerically delineated with a software tool. Based on ICESat observations, we analyse the characteristics of water level variation in different geographic environments, as well as investigate the reasons for the variation. Results indicate that climatic warming contributes to rising water levels in lakes in mountainous areas, especially for lakes that are recharged by snow and glacial melting. For lakes in oases, the water levels are affected jointly by human activity and climate change, while the water levels of reservoirs are mainly affected by human activity. Comparing the annual average rates of water levels, those of lakes are higher than those of reservoirs in oasis areas. The main reasons for the decreasing water levels in desert regions are the reduction of recharged runoff and high evaporation. By analysing the variation of water levels and water volume in different geologic environments, it is found that water level and volume increased in mountainous regions, and decreased in oasis regions and desert regions. Finding also demonstrate that decreasing volume is greater than increasing volume, which results in decreasing total volume of Xinjiang lakes and reservoirs. PMID:28873094

Anesthesia in a Combat Environment

DTIC Science & Technology

1981-09-25

infusion in those patients where disruption of iliac vei~ns or inferior vena cava is a possibility (pelvic, abdominal, or chest trauima), A cathetor...minimal or no decrease in cardiac output, stroke volume, left -ventricular work, stroke work, and mean arterial pressure (5). Halothane, fluroxene, and...healthy young male volunteers to preserve cardiac output unchanged, decrease stroke volume, arterial pressure, peripheral resistance, 02 and left

Acute decrease of left ventricular mechanical dyssynchrony and improvement of contractile state and energy efficiency after left ventricular restoration.

PubMed

Schreuder, Jan J; Castiglioni, Alessandro; Maisano, Francesco; Steendijk, Paul; Donelli, Andrea; Baan, Jan; Alfieri, Ottavio

2005-01-01

Surgical left ventricular restoration by means of endoventricular patch aneurysmectomy in patients with postinfarction aneurysm should result in acute improved left ventricular performance by decreasing mechanical dyssynchrony and increasing energy efficiency. Nine patients with left ventricular postinfarction aneurysm were studied intraoperatively before and after ventricular restoration with a conductance volume catheter to analyze pressure-volume relationships, energy efficiency, and mechanical dyssynchrony. The end-systolic elastance was used as a load-independent index of contractile state. Left ventricular energy efficiency was calculated from stroke work and total pressure-volume area. Segmental volume changes perpendicular to the long axis were used to calculate mechanical dyssynchrony. Statistical analysis was performed with the paired t test and least-squares linear regression. Endoventricular patch aneurysmectomy reduced end-diastolic volume by 37% (P < .001), with unchanged stroke volume. Systolic function improved, as derived from increased +dP/dt(max), by 42% (P < .03), peak ejection rate by 28% (P < .02), and ejection fraction by 16% (P < .0002). Early diastolic function improved, as shown by reduction of -dP/dt(max) by 34% (P < .006) and shortened tau by 30% (P < .001). Left ventricular end-systolic elastance increased from 1.2 +/- 0.6 to 2.2 +/- 1 mm Hg/mL (P < .001). Left ventricular energy efficiency increased by 36% (P < .002). Left ventricular mechanical dyssynchrony decreased during systole by 33% (P < .001) and during diastole by 20% (P < .005). Left ventricular restoration induced acute improvements in contractile state, energy efficiency, and relaxation, together with a decrease in left ventricular mechanical dyssynchrony.

Dissolution and secondary mineral precipitation in basalts due to reactions with carbonic acid

NASA Astrophysics Data System (ADS)

Kanakiya, Shreya; Adam, Ludmila; Esteban, Lionel; Rowe, Michael C.; Shane, Phil

2017-06-01

One of the leading hydrothermal alteration processes in volcanic environments is when rock-forming minerals with high concentrations of iron, magnesium, and calcium react with CO2 and water to form carbonate minerals. This is used to the advantage of geologic sequestration of anthropogenic CO2. Here we experimentally investigate how mineral carbonation processes alter the rock microstructure due to CO2-water-rock interactions. In order to characterize these changes, CO2-water-rock alteration in Auckland Volcanic Field young basalts (less than 0.3 Ma) is studied before and after a 140 day reaction period. We investigate how whole core basalts with similar geochemistry but different porosity, permeability, pore geometry, and volcanic glass content alter due to CO2-water-rock reactions. Ankerite and aluminosilicate minerals precipitate as secondary phases in the pore space. However, rock dissolution mechanisms are found to dominate this secondary mineral precipitation resulting in an increase in porosity and decrease in rigidity of all samples. The basalt with the highest initial porosity and volcanic glass volume shows the most secondary mineral precipitation. At the same time, this sample exhibits the greatest increase in porosity and permeability, and a decrease in rock rigidity post reaction. For the measured samples, we observe a correlation between volcanic glass volume and rock porosity increase due to rock-fluid reactions. We believe this study can help understand the dynamic rock-fluid interactions when monitoring field scale CO2 sequestration projects in basalts.

The study of the structural features of the lymphocytes from cattle with and without retroviral infection using atomic force microscopy

NASA Astrophysics Data System (ADS)

Artemev, Dmitry A.; Krasnikova, Ekaterina S.; Stolbovskaya, Olga V.; Krasnikov, Aleksandr V.; Kostishko, Boris B.; Roman, Radionov V.

2018-04-01

The results of the study of morphological and biophysical parameters of cell membranes of fixed lymphocytes from cattle with and without retroviral infection using atomic force microscopy have been presented. It is found that lymphocytes morphometric characteristics, such as diameter, height, volume, in case of BLV and BIV-BLV infection decrease by 18.5 and 22.7%, 9.0 and 25.0%, 4.4 and 35.3%, respectively, in comparison with the intact ones. It is maybe a sign of the cells immaturity or the degenerative processes development. However, the lymphocytes' morphometric characteristics in case of BIV infection increase by 45.8%, 12.7% and 35.8%, respectively, compared with the intact lymphocytes. It may be caused by the active replicative processes in BIV-infected cells. It is found that the adhesive properties and the roughness of cell surface of the lymphocytes from cattle with BLV, BIV, BIV-BLV infection increase in 2.3, 3.4, 3.0 times and by 37.3%, 19.2%, 14.8%, respectively, in comparison with the control cows' lymphocytes. A decrease in the Young's modulus of lymphocytes from cattle with BIV, BLV and BIV-BLV infection of 35.8%, 33.8% and 33.1%, respectively, compared to the control has been shown. It may indicate not only an increase in the cytolemma stiffness, but also an increase in the cell turgor as a result of volume index raising.

The Effect of Drying-Wetting Cycle’s Repetition to the Characteristic of Natural and Stabilization Residual Soils Jawa Timur - Indonesia

NASA Astrophysics Data System (ADS)

Muntaha, M.

2017-11-01

Indonesia, which located in tropical region, continuously undergoes wetting and drying cycles due to the changeable seasons. An important role in activating the clay minerals on tropical residual soils is the main factor that affects the static and dynamic properties, such as: volume change, soil suction and dynamic modulus. The purpose of this paper is to evaluate the effect of drying-wetting cycles repetition on volume change, soil suction and mechanical characteristics of natural and stabilization of residual soils from Jawa Timur - Indonesia. The natural undisturbed and stabilized residual soil sample was naturally and gradually dried up with air to 25%, 50%, 75%, and 100 % of the initial water content. The wetting processes were carried out with the gradual increment water content of 25 %(wsat - wi), 50 %(wsat - wi), 75 %(wsat - wi), up to 100 %(wsat - wi). The Direct Shear test is used to measure the mechanic properties, and Whatman filter paper No. 42 is used to measure the soil suction. The drying-wetting processes were carried out for 1, 2, 4, and 6 cycles. The laboratory test results showed that, the void ratio decreased, the unit weight, cohesion and the internal friction angle were increasing due to stabilization. Drying-wetting cycle repetition reduces void ratio, negative pore-water pressure, cohesion and internal friction angle of natural and stabilized soils. Briefly, the decreased of mechanical soil properties was proven from the physical properties change observation.

Effects of crosslinking on the mechanical properties, drug release and cytocompatibility of protein polymers.

PubMed

Martinez, Adam W; Caves, Jeffrey M; Ravi, Swathi; Li, Wehnsheng; Chaikof, Elliot L

2014-01-01

Recombinant elastin-like protein polymers are increasingly being investigated as component materials of a variety of implantable medical devices. This is chiefly a result of their favorable biological properties and the ability to tailor their physical and mechanical properties. In this report, we explore the potential of modulating the water content, mechanical properties, and drug release profiles of protein films through the selection of different crosslinking schemes and processing strategies. We find that the selection of crosslinking scheme and processing strategy has a significant influence on all aspects of protein polymer films. Significantly, utilization of a confined, fixed volume, as well as vapor-phase crosslinking strategies, decreased protein polymer equilibrium water content. Specifically, as compared to uncrosslinked protein gels, water content was reduced for genipin (15.5%), glutaraldehyde (GTA, 24.5%), GTA vapor crosslinking (31.6%), disulfide (SS, 18.2%) and SS vapor crosslinking (25.5%) (P<0.05). Distinct crosslinking strategies modulated protein polymer stiffness, strain at failure and ultimate tensile strength (UTS). In all cases, vapor-phase crosslinking produced the stiffest films with the highest UTS. Moreover, both confined, fixed volume and vapor-phase approaches influenced drug delivery rates, resulting in decreased initial drug burst and release rates as compared to solution phase crosslinking. Tailored crosslinking strategies provide an important option for modulating the physical, mechanical and drug delivery properties of protein polymers. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Application of novel Modified Biological Aerated Filter (MBAF) as a promising post-treatment for water reuse: Modification in configuration and backwashing process.

PubMed

Nikoonahad, Ali; Ghaneian, Mohammad Taghi; Mahvi, Amir Hossein; Ehrampoush, Mohammad Hassan; Ebrahimi, Ali Asghar; Lotfi, Mohammad Hassan; Salamehnejad, Sima

2017-12-01

Biological Aerated Filter (BAF) reactors due to their plentiful biomass, high shockability, high efficiency, good filtration, availability and lack of need for large land areas, are enjoying from great importance in advanced wastewater treatment. Therefore, in this study, Polystyrene Coated by Sand (PCS) was produced as a novel media and its application in a modified down-flow BAF structure for advanced wastewater treatment was assessed in two steps. In step one, the backwash effluent did not return to the system, while in step two backwash effluent returned to increase the water reuse efficiency. The backwash process was also studied through three methods of Top Backwashing (TB), Bottom Backwashing (BB), as well as Top and Bottom Backwashing Simultaneously (TBBS). The results showed that return of backwash effluent had no significant effect on the BAF effluent quality. In the second step similar to the first one with slight differences, the residual average concentrations of TSS, BOD 5 , and COD at the effluent were about 2.5, 8.2, and 25.5 mg/L, respectively. Additionally, in step two, the mean volume of disposal sludge/volume of treated water (v ds /v tw ) decreased a large extent to about 0.088%. In other words, the water reuse has increased to more than 99.91%. The backwash time in methods of TB and BB were 65 and 35 min, respectively; however, it decreased in TBBS methods to 25 min. The concentrations of most effluent parameters in this system are in concordance with the 2012 EPA Agriculture Standards, even for irrigation of Non-processed agricultural crops and livestock water consumption. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of aeration rate and waste load on evolution of volatile fatty acids and waste stabilization during thermophilic aerobic digestion of a model high strength agricultural waste.

PubMed

Ugwuanyi, J Obeta; Harvey, L M; McNeil, B

2005-04-01

Thermophilic aerobic digestion (TAD) is a relatively new, dynamic and versatile low technology for the economic processing of high strength waste slurries. Waste so treated may be safely disposed of or reused. In this work a model high strength agricultural waste, potato peel, was subjected to TAD to study the effects of oxygen supply at 0.1, 0.25, 0.5 and 1.0 vvm (volume air per volume slurry per minute) under batch conditions at 55 degrees C for 156 h on the process. Process pH was controlled at 7.0 or left unregulated. Effects of waste load, as soluble chemical oxygen demand (COD), on TAD were studied at 4.0, 8.0, 12.0 and 16.0 gl(-1) (soluble COD) at pH 7.0, 0.5 vvm and 55 degrees C. Efficiency of treatment, as degradation of total solids, total suspended solids and soluble solid, as well as soluble COD significantly increased with aeration rate, while acetate production increased as the aeration rate decreased or waste load increased, signifying deterioration in treatment. Negligible acetate, and no other acids were produced at 1.0 vvm. Production of propionate and other acids increased after acetate concentration had started to decrease and, during unregulated reactions coincided with the drop in the pH of the slurry. Acetate production was more closely associated with periods of oxygen limitation than were other acids. Reduction in oxygen availability led to deterioration in treatment efficiency as did increase in waste load. These variables may be manipulated to control treated waste quality.

Development and investigation of single-scan TV radiography for the acquisition of dynamic physiologic data

NASA Technical Reports Server (NTRS)

Baily, N. A.

1975-01-01

A light amplifier for large flat screen fluoroscopy was investigated which will decrease both its size and weight. The work on organ contouring was extended to yield volumes. This is a simple extension since the fluoroscopic image contains density (gray scale) information which can be translated as tissue thickness, integrated, yielding accurate volume data in an on-line situation. A number of devices were developed for analog image processing of video signals, operating on-line in real time, and with simple selection mechanisms. The results show that this approach is feasible and produces are improvement in image quality which should make diagnostic error significantly lower. These are all low cost devices, small and light in weight, thereby making them usable in a space environment, on the Ames centrifuge, and in a typical clinical situation.

Effect of Pertalite-Spiritus Blend Fuel on Performance of Single Cylinder Spark Ignition Engine

NASA Astrophysics Data System (ADS)

Wibowo, H.; Susastriawan, A. A. P.; Andrian, D.

2018-02-01

This work aims to experimentally investigate an effect of Spiritus and Pertalite blend on engine’s performance (brake horsepower and torque, specific fuel consumption rate, and exhaust gas emission). The tests are conducted at 3000-7000 rpm for four different fuels, i.e., pertalite, 95%P-5%S, 90%P-10%S, and 85%P-15%S to obtain an optimum ratio of the Pertalite-Spiritus blend. The blend ratios of Pertalite (P) and Spiritus (S) are measured by volume. The result shows that addition of 15% Spiritus (by volume) on Pertalilte can enhance the combustion process of the blend hence increasing engine’s brake horsepower and decreasing specific fuel consumption rate. However, engine’s torque is lower when using the blend 85%P-15%S if compared with using Pertalite.

23.4% saline decreases brain tissue volume in severe hepatic encephalopathy as assessed by a quantitative computed tomography marker

PubMed Central

Liotta, Eric M; Lizza, Bryan D; Romanova, Anna L; Guth, James C; Berman, Michael D; Carroll, Timothy J; Francis, Brandon; Ganger, Daniel; Ladner, Daniela P; Maas, Matthew B; Naidech, Andrew M

2016-01-01

Objective Cerebral edema is common in severe hepatic encephalopathy and may be life-threatening. Bolus 23.4% hypertonic saline (HTS) improves surveillance neuromonitoring scores, although its mechanism of action is not clearly established. We investigated the hypothesis that bolus HTS decreases cerebral edema in severe hepatic encephalopathy utilizing a quantitative technique to measure brain and CSF volume changes. Design Retrospective analysis of serial computed tomography (CT) scans and clinical data for a case-control series was performed. Setting Intensive care units of a tertiary care hospital. Patients Patients with severe hepatic encephalopathy treated with 23.4% HTS and control patients who did not receive 23.4% HTS. Methods We used clinically obtained CT scans to measure volumes of the ventricles, intracranial CSF, and brain using a previously validated semi-automated technique (Analyze Direct; Overland Park, KS). Volumes before and after 23.4% HTS were compared with Wilcoxon signed-rank test. Associations between total CSF volume, ventricular volume, serum sodium, and Glasgow Coma Scale Scores were assessed using Spearman correlation. Results Eleven patients with 18 administrations of 23.4% HTS met inclusion criteria. Total CSF (median 47.6 [35.1–69.4] to 61.9 [47.7–87.0] mL, p<0.001) and ventricular volumes (median 8.0 [6.9–9.5] to 9.2 [7.8–11.9] mL, p=0.002) increased and Glasgow Coma Scale Scores improved (median 4 [3–6] to 7 [6–9], p=0.008) after 23.4% HTS. In contrast, total CSF and ventricular volumes decreased in untreated control patients. Serum sodium increase was associated with increase in total CSF volume (r=0.83, p<0.001) and change in total CSF volume was associated with ventricular volume change (r=0.86, p<0.001). Conclusions Total CSF and ventricular volumes increased after 23.4% HTS, consistent with a reduction in brain tissue volume. Total CSF and ventricular volume change may be useful quantitative measures to assess cerebral edema in severe hepatic encephalopathy. PMID:26308431

INCREASED MYOCARDIAL STIFFNESS DUE TO CARDIAC TITIN ISOFORM SWITCHING IN A MOUSE MODEL OF VOLUME OVERLOAD LIMITS ECCENTRIC REMODELING

PubMed Central

Hutchinson, Kirk R; Saripalli, Chandra; Chung, Charles S.; Granzier, Henk

2014-01-01

We investigated the cellular and molecular mechanisms of diastolic dysfunction in pure volume overload induced by aortocaval fistula (ACF) surgery in the mouse. Four weeks of volume overload resulted in significant biventricular hypertrophy; protein expression analysis in left ventricular (LV) tissue showed a marked decrease in titin's N2BA/N2B ratio with no change in phosphorylation of titin's spring region. Titin-based passive tensions were significantly increased; a result of the decreased N2BA/N2B ratio. Conscious echocardiography in ACF mice revealed eccentric remodeling and pressure volume analysis revealed systolic dysfunction: reductions in ejection fraction (EF), +dP/dt, and the slope of the endsystolic pressure volume relationships (ESPVR). ACF mice also had diastolic dysfunction: increased LV end-diastolic pressure and reduced relaxation rates. Additionally, a decrease in the slope of the end diastolic pressure volume relationship (EDPVR) was found. However, correcting for altered geometry of the LV normalized the change in EDPVR and revealed, in line with our skinned muscle data, increased myocardial stiffness in vivo. ACF mice also had increased expression of the signaling proteins FHL-1, FHL-2, and CARP that bind to titin's spring region suggesting that titin stiffening is important to the volume overload phenotype. To test this we investigated the effect of volume overload in the RBM20 heterozygous (HET) mouse model, which exhibits reduced titin stiffness. It was found that LV hypertrophy was attenuated and that LV eccentricity was exacerbated. We propose that pure volume overload induces an increase in titin stiffness that is beneficial and limits eccentric remodeling. PMID:25450617

The Influence of Changes in Tumor Hypoxia on Dose-Painting Treatment Plans Based on {sup 18}F-FMISO Positron Emission Tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin Zhixiong; Mechalakos, James; Nehmeh, Sadek

2008-03-15

Purpose: To evaluate how changes in tumor hypoxia, according to serial fluorine-18-labeled fluoro-misonidazole ({sup 18}F-FMISO) positron emission tomography (PET) imaging, affect the efficacy of intensity-modulated radiotherapy (IMRT) dose painting. Methods and Materials: Seven patients with head and neck cancers were imaged twice with FMISO PET, separated by 3 days, before radiotherapy. Intensity-modulated radiotherapy plans were designed, on the basis of the first FMISO scan, to deliver a boost dose of 14 Gy to the hypoxic volume, in addition to the 70-Gy prescription dose. The same plans were then applied to hypoxic volumes from the second FMISO scan, and the efficacymore » of dose painting evaluated by assessing coverage of the hypoxic volumes using D{sub max}, D{sub min}, D{sub mean}, D{sub 95}, and equivalent uniform dose (EUD). Results: Similar hypoxic volumes were observed in the serial scans for 3 patients but dissimilar ones for the other 4. There was reduced coverage of hypoxic volumes of the second FMISO scan relative to that of the first scan (e.g., the average EUD decreased from 87 Gy to 80 Gy). The decrease was dependent on the similarity of the hypoxic volumes of the two scans (e.g., the average EUD decrease was approximately 4 Gy for patients with similar hypoxic volumes and approximately 12 Gy for patients with dissimilar ones). Conclusions: The changes in spatial distribution of tumor hypoxia, as detected in serial FMISO PET imaging, compromised the coverage of hypoxic tumor volumes achievable by dose-painting IMRT. However, dose painting always increased the EUD of the hypoxic volumes.« less

Development of porous titanium for biomedical applications: A comparison between loose sintering and space-holder techniques.

PubMed

Torres, Yadir; Lascano, Sheila; Bris, Jorge; Pavón, Juan; Rodriguez, José A

2014-04-01

One of the most important concerns in long-term prostheses is bone resorption as a result of the stress shielding due to stiffness mismatch between bone and implant. The aim of this study was to obtain porous titanium with stiffness values similar to that exhibited by cortical bone. Porous samples of commercial pure titanium grade-4 were obtained by following both loose-sintering processing and space-holder technique with NaCl between 40 and 70% in volume fraction. Both mechanical properties and porosity morphology were assessed. Young's modulus was measured using uniaxial compression testing, as well as ultrasound methodology. Complete characterization and mechanical testing results allowed us to determine some important findings: (i) optimal parameters for both processing routes; (ii) better mechanical response was obtained by using space-holder technique; (iii) pore geometry of loose sintering samples becomes more regular with increasing sintering temperature; in the case of the space-holder technique that trend was observed for decreasing volume fraction; (iv) most reliable Young's modulus measurements were achieved by ultrasound technique. Copyright © 2013 Elsevier B.V. All rights reserved.

Dynamics of the microglial/amyloid interaction indicate a role in plaque maintenance.

PubMed

Bolmont, Tristan; Haiss, Florent; Eicke, Daniel; Radde, Rebecca; Mathis, Chester A; Klunk, William E; Kohsaka, Shinichi; Jucker, Mathias; Calhoun, Michael E

2008-04-16

Microglial cells aggregate around amyloid plaques in Alzheimer's disease, but, despite their therapeutic potential, various aspects of their reactive kinetics and role in plaque pathogenesis remain hypothetical. Through use of in vivo imaging and quantitative morphological measures in transgenic mice, we demonstrate that local resident microglia rapidly react to plaque formation by extending processes and subsequently migrating toward plaques, in which individual transformed microglia somata remain spatially stable for weeks. The number of plaque-associated microglia increased at a rate of almost three per plaque per month, independent of plaque volume. Larger plaques were surrounded by larger microglia, and a subset of plaques changed in size over time, with an increase or decrease related to the volume of associated microglia. Far from adopting a more static role, plaque-associated microglia retained rapid process and membrane movement at the plaque/glia interface. Microglia internalized systemically injected amyloid-binding dye at a much higher rate in the vicinity of plaques. These results indicate a role for microglia in plaque maintenance and provide a model with multiple targets for therapeutic intervention.

Dynamics of the Microglial/Amyloid Interaction Indicate a Role in Plaque Maintenance

PubMed Central

Bolmont, Tristan; Haiss, Florent; Eicke, Daniel; Radde, Rebecca; Mathis, Chester A.; Klunk, William E.; Kohsaka, Shinichi; Jucker, Mathias

2008-01-01

Microglial cells aggregate around amyloid plaques in Alzheimer's disease, but, despite their therapeutic potential, various aspects of their reactive kinetics and role in plaque pathogenesis remain hypothetical. Through use of in vivo imaging and quantitative morphological measures in transgenic mice, we demonstrate that local resident microglia rapidly react to plaque formation by extending processes and subsequently migrating toward plaques, in which individual transformed microglia somata remain spatially stable for weeks. The number of plaque-associated microglia increased at a rate of almost three per plaque per month, independent of plaque volume. Larger plaques were surrounded by larger microglia, and a subset of plaques changed in size over time, with an increase or decrease related to the volume of associated microglia. Far from adopting a more static role, plaque-associated microglia retained rapid process and membrane movement at the plaque/glia interface. Microglia internalized systemically injected amyloid-binding dye at a much higher rate in the vicinity of plaques. These results indicate a role for microglia in plaque maintenance and provide a model with multiple targets for therapeutic intervention. PMID:18417708

Physiological Effects of Training.

DTIC Science & Technology

1985-06-25

applies only to short-term programs, the resting heart rate is norrally reduced as a result of aerobic training in all age groups. I0 Studies with ...in order to maintain cardiao output in conjunction with a decreased heart rate, stroke volume has to Increase. Stroke volume increases in the...volume is partially due too increased end diastolic volume. Thus, the pumping ability of the heart , I.e. increased stroke volume, is improved with

Increased muscular volume and cuticular specialisations enhance jump velocity in solitarious compared with gregarious desert locusts, Schistocerca gregaria.

PubMed

Rogers, Stephen M; Riley, Joanna; Brighton, Caroline; Sutton, Gregory P; Cullen, Darron A; Burrows, Malcolm

2016-03-01

The desert locust, Schistocerca gregaria, shows a strong phenotypic plasticity. It can develop, depending upon population density, into either a solitarious or gregarious phase that differs in many aspects of behaviour, physiology and morphology. Prominent amongst these differences is that solitarious locusts have proportionately longer hind femora than gregarious locusts. The hind femora contain the muscles and energy-storing cuticular structures that propel powerful jumps using a catapult-like mechanism. We show that solitarious locusts jump on average 23% faster and 27% further than gregarious locusts, and attribute this improved performance to three sources: first, a 17.5% increase in the relative volume of their hind femur, and hence muscle volume; second, a 24.3% decrease in the stiffness of the energy-storing semi-lunar processes of the distal femur; and third, a 4.5% decrease in the stiffness of the tendon of the extensor tibiae muscle. These differences mean that solitarious locusts can generate more power and store more energy in preparation for a jump than can gregarious locusts. This improved performance comes at a cost: solitarious locusts expend nearly twice the energy of gregarious locusts during a single jump and the muscular co-contraction that energises the cuticular springs takes twice as long. There is thus a trade-off between achieving maximum jump velocity in the solitarious phase against the ability to engage jumping rapidly and repeatedly in the gregarious phase. © 2016. Published by The Company of Biologists Ltd.

Methylmercury-induced inhibition of regulatory volume decrease in astrocytes: characterization of osmoregulator efflux and its reversal by amiloride.

PubMed

Aschner, M; Vitarella, D; Allen, J W; Conklin, D R; Cowan, K S

1998-11-16

Swelling of neonatal rat primary astrocyte cultures by hypotonic media leads to regulatory volume decrease (RVD) and the resumption of resting cell volume. RVD is associated with activation of conductive K+ and Cl- channels, allowing for the escape of KCl, as well as the release of osmoregulators, such as taurine and myoinositol. As we have previously shown [D. Vitarella, H.K. Kimelberg, M. Aschner, Inhibition of RVD in swollen rat primary astrocyte cultures by methylmercury (MeHg) is due to increase amiloride-sensitive Na+ uptake, Brain Res. 732 (1996) 169-178.], MeHg, when added to hypotonic buffer inhibits RVD, primarily due to increased cellular permeability to Na+ via the Na+/H+ antiporter. The present study was, therefore, undertaken to assess the ability of cation-anion cotransport blockers to reverse the inhibitory effect of MeHg on RVD in swollen astrocytes, and to further characterize MeHg-induced changes in astrocytic osmoregulatory release processes. The studies demonstrate the following: (1) MeHg-induced inhibition of RVD is partially inhibited by the Na+/H+ antiporter blocker, amiloride, but not SITS (4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid), DIDS (4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid), furosemide or bumetanide; (2) exposure of swollen astrocytes to MeHg is associated with specific effects on osmoregulatory release, leading to significant inhibition of taurine release and a significant increase in potassium and myoinositol release compared with release in hypotonic conditions. Copyright 1998 Elsevier Science B.V.

Hydrologic risk analysis in the Yangtze River basin through coupling Gaussian mixtures into copulas

NASA Astrophysics Data System (ADS)

Fan, Y. R.; Huang, W. W.; Huang, G. H.; Li, Y. P.; Huang, K.; Li, Z.

2016-02-01

In this study, a bivariate hydrologic risk framework is proposed through coupling Gaussian mixtures into copulas, leading to a coupled GMM-copula method. In the coupled GMM-Copula method, the marginal distributions of flood peak, volume and duration are quantified through Gaussian mixture models and the joint probability distributions of flood peak-volume, peak-duration and volume-duration are established through copulas. The bivariate hydrologic risk is then derived based on the joint return period of flood variable pairs. The proposed method is applied to the risk analysis for the Yichang station on the main stream of the Yangtze River, China. The results indicate that (i) the bivariate risk for flood peak-volume would keep constant for the flood volume less than 1.0 × 105 m3/s day, but present a significant decreasing trend for the flood volume larger than 1.7 × 105 m3/s day; and (ii) the bivariate risk for flood peak-duration would not change significantly for the flood duration less than 8 days, and then decrease significantly as duration value become larger. The probability density functions (pdfs) of the flood volume and duration conditional on flood peak can also be generated through the fitted copulas. The results indicate that the conditional pdfs of flood volume and duration follow bimodal distributions, with the occurrence frequency of the first vertex decreasing and the latter one increasing as the increase of flood peak. The obtained conclusions from the bivariate hydrologic analysis can provide decision support for flood control and mitigation.

The impact on revenue of increasing patient volume at surgical suites with relatively high operating room utilization.

PubMed

Dexter, F; Macario, A; Lubarsky, D A

2001-05-01

We previously studied hospitals in the United States of America that are losing money despite limiting the hours that operating room (OR) staff are available to care for patients undergoing elective surgery. These hospitals routinely keep utilization relatively high to maximize revenue. We tested, using discrete-event computer simulation, whether increasing patient volume while being reimbursed less for each additional patient can reliably achieve an increase in revenue when initial adjusted OR utilization is 90%. We found that increasing the volume of referred patients by the amount expected to fill the surgical suite (100%/90%) would increase utilization by <1% for a hospital surgical suite (with longer duration cases) and 4% for an ambulatory surgery suite (with short cases). The increase in patient volume would result in longer patient waiting times for surgery and more patients leaving the surgical queue. With a 15% reduction in payment for the new patients, the increase in volume may not increase revenue and can even decrease the contribution margin for the hospital surgical suite. The implication is that for hospitals with a relatively high OR utilization, signing discounted contracts to increase patient volume by the amount expected to "fill" the OR can have the net effect of decreasing the contribution margin (i.e., profitability). Hospitals may try to attract new surgical volume by offering discounted rates. For hospitals with a relatively high operating room utilization (e.g., 90%), computer simulations predict that increasing patient volume by the amount expected to "fill" the operating room can have the net effect of decreasing contribution margin (i.e., profitability).

Causes of hot-spot wetland loss in the Mississippi delta plain

USGS Publications Warehouse

Morton, R.A.; Tiling, G.; Ferina, N.F.

2003-01-01

Field surveys and sediment cores were used to estimate marsh erosion and land subsidence at Madison Bay, a well-known wetland loss hot spot in coastal Louisiana. Former marshes of Madison Bay are under about 1 m of water. Nearly two-thirds of the permanent flooding was caused by rapid subsidence in the late 1960s, whereas the other third was caused by subsequent erosion. Subsidence rates near Madison Bay since the 1960s (???20 mm/yr) are an order of magnitude greater than deltaic subsidence rates averaged for the past 400-4000 yr (???2 mm/yr). The rapid acceleration and unexpected decline in wetland losses in the Mississippi delta plain are difficult to explain on the basis of most physical and biogeochemical processes. There are, however, close temporal and spatial correlations among regional wetland loss, high subsidence rates, and large-volume fluid production from nearby hydrocarbon fields. The decreased rates of wetland loss since the 1970s may be related to decreased rates of subsidence caused by significantly decreased rates of subsurface fluid withdrawal. Annual fluid production from the Lapeyrouse, Lirette, and Bay Baptiste fields that encompass Madison Bay accelerated in the 1960s, peaked about 1970, and then declined abruptly. Large decreases in pore pressure in the Lapeyrouse field have likely altered subsurface stresses and reactivated a major fault that coincides with the wetland loss hot spot. Therefore, wetland losses at Madison Bay can be closely linked to rapid subsidence and possible fault reactivation induced by long-term, large-volume hydrocarbon production. ?? 2003. The American Association of Petroleum Geologists/Division of Environmental Geosciences. All rights reserved.

Investigations in Producing Porous NiAl by Combustion Synthesis

NASA Astrophysics Data System (ADS)

Zhong, Songming

In recent years, nickel aluminide (NiAl) intermetallic foam, which combines the advantages of nickel-based alloy and metallic foam, has attracted great attention due to its extraordinary properties. In this present work, nickel aluminide (NiAl) foam has been reactively processed from elemental powder (nickel and aluminium) with different types and percentage of volume of a foaming agent (TiH2 or CaCO3), using a combustion synthesis (CS) approach. Most of the previous research has focused on producing close-cell NiAl intermetallic foam; however, this paper presents a new combustion synthesis process to fabricate a hybrid open-cell and close-cell NiAl intermetallic foam. Mixed elemental powder was compacted at moderate pressure generating closed and open porosity with green compact; as a result, part of the liberated gas could escape from the sample, which resulted in producing open-cell pores, in addition, closed cell pores in the product. The effect of foaming agent type and volume percentage on the product is discussed. An increase in volume percentage of TiH2 was found to have beneficial effects on increasing porosity; however, with the increase of volume percentage of CaCO3, there is a big drop in porosity because the low viscosity under high temperature makes more liberated gas escape and pores collapse. According to XRD and EDX analysis, despite the present of multiple phases in samples, NiAl was still the major phase. Hardness measurement shows that high hardness value was obtained at sample of low grain size, hardness value increases with decreasing grain size.

Controls on Martian Hydrothermal Systems: Application to Valley Network and Magnetic Anomaly Formation

NASA Technical Reports Server (NTRS)

Harrison, Keith P.; Grimm, Robert E.

2002-01-01

Models of hydrothermal groundwater circulation can quantify limits to the role of hydrothermal activity in Martian crustal processes. We present here the results of numerical simulations of convection in a porous medium due to the presence of a hot intruded magma chamber. The parameter space includes magma chamber depth, volume, aspect ratio, and host rock permeability and porosity. A primary goal of the models is the computation of surface discharge. Discharge increases approximately linearly with chamber volume, decreases weakly with depth (at low geothermal gradients), and is maximized for equant-shaped chambers. Discharge increases linearly with permeability until limited by the energy available from the intrusion. Changes in the average porosity are balanced by changes in flow velocity and therefore have little effect. Water/rock ratios of approximately 0.1, obtained by other workers from models based on the mineralogy of the Shergotty meteorite, imply minimum permeabilities of 10(exp -16) sq m2 during hydrothermal alteration. If substantial vapor volumes are required for soil alteration, the permeability must exceed 10(exp -15) sq m. The principal application of our model is to test the viability of hydrothermal circulation as the primary process responsible for the broad spatial correlation of Martian valley networks with magnetic anomalies. For host rock permeabilities as low as 10(exp -17) sq m and intrusion volumes as low as 50 cu km, the total discharge due to intrusions building that part of the southern highlands crust associated with magnetic anomalies spans a comparable range as the inferred discharge from the overlying valley networks.

Circulatory failure during severe hyperthermia in dog.

PubMed

Miki, K; Morimoto, T; Nose, H; Itoh, T; Yamada, S

1983-01-01

The effect of acute hyperthermia on circulatory function was studied in 6 mongrel dogs. At a core temperature of about 40 degrees C, central venous pressure and stroke volume were maintained at almost normal level. Cardiac output significantly increased (26 ml/(kg . min)) while systemic vascular resistance significantly decreased (1.2 mmHg . sec/ml). In addition, significant decrease in vascular compliance by 40% was observed. When body temperature was raised further (severe hyperthermia), an abrupt fall of arterial pressure was observed at the rectal temperature of about 41-42 degrees C. Concomitant decreases in central venous pressure (3 mmHg), stroke volume (2.1 ml/beat) and cardiac output (29 ml/(kg . min)) were observed while heart rate increased (48 beats/min). These results suggest that the decrease in cardiac output during severe hyperthermia is due to the fall of central venous pressure, and the fall was attributed to the increase in unstressed vascular volume of systemic circulation due to the heat-induced cutaneous vasodilation. The observed decrease in systemic vascular compliance is considered to have a significant role in the maintenance of central venous pressure under hyperthermia.

[A simple model for describing pressure-volume curves in free balloon dilatation with reference the dynamics of inflation hydraulic aspects].

PubMed

Bloss, P; Werner, C

2000-06-01

We propose a simple model to describe pressure-time and pressure-volume curves for the free balloon (balloon in air) of balloon catheters, taking into account the dynamics of the inflation device. On the basis of our investigations of the flow rate-dependence of characteristic parameters of the pressure-time curves, the appropriateness of this simple model is demonstrated using a representative example. Basic considerations lead to the following assumptions: (1) the flow within the shaft of the catheter is laminar, and (ii) the volume decrease of the liquid used for inflation due to pressurization can be neglected if the liquid is carefully degassed prior to inflation, and if the total volume of the liquid in the system is less than 2 ml. Taking into account the dynamics of the inflation device used for pumping the liquid into the proximal end of the shaft during inflation, the inflation process can be subdivided into the following three phases: initial phase, filling phase and dilatation phase. For these three phases, the transformation of the time into the volume coordinates is given. On the basis of our model, the following parameters of the balloon catheter can be determined from a measured pressure-time curve: (1) the resistance to flow of the liquid through the shaft of the catheter and the resulting pressure drop across the shaft, (2) the residual volume and residual pressure of the balloon, and (3) the volume compliance of the balloon catheter with and without the inflation device.

The non-diuretic hypotensive effects of thiazides are enhanced during volume depletion states

PubMed Central

Alshahrani, Saeed; Rapoport, Robert M.; Zahedi, Kamyar; Jiang, Min; Nieman, Michelle; Barone, Sharon; Meredith, Andrea L.; Lorenz, John N.; Rubinstein, Jack

2017-01-01

Thiazide derivatives including Hydrochlorothiazide (HCTZ) represent the most common treatment of mild to moderate hypertension. Thiazides initially enhance diuresis via inhibition of the kidney Na+-Cl- Cotransporter (NCC). However, chronic volume depletion and diuresis are minimal while lowered blood pressure (BP) is maintained on thiazides. Thus, a vasodilator action of thiazides is proposed, likely via Ca2+-activated K+ (BK) channels in vascular smooth muscles. This study ascertains the role of volume depletion induced by salt restriction or salt wasting in NCC KO mice on the non-diuretic hypotensive action of HCTZ. HCTZ (20mg/kg s.c.) lowered BP in 1) NCC KO on a salt restricted diet but not with normal diet; 2) in volume depleted but not in volume resuscitated pendrin/NCC dKO mice; the BP reduction occurs without any enhancement in salt excretion or reduction in cardiac output. HCTZ still lowered BP following treatment of NCC KO on salt restricted diet with paxilline (8 mg/kg, i.p.), a BK channel blocker, and in BK KO and BK/NCC dKO mice on salt restricted diet. In aortic rings from NCC KO mice on normal and low salt diet, HCTZ did not alter and minimally decreased maximal phenylephrine contraction, respectively, while contractile sensitivity remained unchanged. These results demonstrate 1) the non-diuretic hypotensive effects of thiazides are augmented with volume depletion and 2) that the BP reduction is likely the result of HCTZ inhibition of vasoconstriction through a pathway dependent on factors present in vivo, is unrelated to BK channel activation, and involves processes associated with intravascular volume depletion. PMID:28719636

Atrial natriuretic peptide decreases blood volume in intact and anephric rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trippodo, N.C.; Chien, Y.W.; Pegram, B.L.

1986-03-05

Atrial natriuretic peptide (ANP) reportedly lowers atrial pressure and increases hematocrit, suggesting venodilation and/or decreased blood volume (BV). To examine these possibilities, rat ANP (99-126) was administered to Inactinanesthetized rats (313 +/- 9 g, +/- SE) at 0.5 ..mu..g/kg/min for 30 minutes. Urine flow increased by 0.05 ml/min (p < 0.001) during the last 15 minutes of infusion. Mean arterial pressure (MAP) and thoracic central venous pressure (CVP) decreased (p < 0.001) by 12 and 0.5 mmHg, respectively; hematocrit increased by 4.1 units (p < 0.001) and BV (/sup 51/Cr-RBC) decreased by 3.4 ml/kg (p < 0.001). Mean circulatory fillingmore » pressure, measured by inflating an intracardiac balloon to briefly stop the circulation, did not change. Distribution of BV between the thoracic and spanchnic organs (whole-animal freezing in liquid nitrogen) was not measurably altered. The results suggest that the decrease in CVP was related more to decreased BV than to venodilation. To investigate possible mechanisms for the decreased BV, the same dose of ANP was administered to anephric rats. MAP decreased by 8 mmHg (p < 0.001); hematocrit increased by 2.4 units (p < 0.001) and BV decreased by 1.7 ml/kg (p < 0.05). The results indicate that short-term administration of ANP decreases blood volume by causing intravascular fluid to shift into the interstitium as well as by inducing diuresis.« less

HIGH VOLUME INJECTION FOR GCMS ANALYSIS OF PARTICULATE ORGANIC SPECIES IN AMBIENT AIR

EPA Science Inventory

Detection of organic species in ambient particulate matter typically requires large air sample volumes, frequently achieved by grouping samples into monthly composites. Decreasing the volume of air sample required would allow shorter collection times and more convenient sample c...

The role of testosterone and estradiol in brain volume changes across adolescence: a longitudinal structural MRI study.

PubMed

Herting, Megan M; Gautam, Prapti; Spielberg, Jeffrey M; Kan, Eric; Dahl, Ronald E; Sowell, Elizabeth R

2014-11-01

It has been postulated that pubertal hormones may drive some neuroanatomical changes during adolescence, and may do so differently in girls and boys. Here, we use growth curve modeling to directly assess how sex hormones [testosterone (T) and estradiol (E₂)] relate to changes in subcortical brain volumes utilizing a longitudinal design. 126 adolescents (63 girls), ages 10 to 14, were imaged and restudied ∼2 years later. We show, for the first time, that best-fit growth models are distinctly different when using hormones as compared to a physical proxy of pubertal maturation (Tanner Stage) or age, to predict brain development. Like Tanner Stage, T and E₂ predicted white matter and right amygdala growth across adolescence in both sexes, independent of age. Tanner Stage also explained decreases in both gray matter and caudate volumes, whereas E₂ explained only gray matter decreases and T explained only caudate volume decreases. No pubertal measures were related to hippocampus development. Although specificity was seen, sex hormones had strikingly similar relationships with white matter, gray matter, right amygdala, and bilateral caudate volumes, with larger changes in brain volume seen at early pubertal maturation (as indexed by lower hormone levels), followed by less robust, or even reversals in growth, by late puberty. These novel longitudinal findings on the relationship between hormones and brain volume change represent crucial first steps toward understanding which aspects of puberty influence neurodevelopment. Copyright © 2014 Wiley Periodicals, Inc.

Renal sodium reabsorption following induction of and recovery from volume expansion

NASA Technical Reports Server (NTRS)

Knight, T. F.; Weinman, E. J.

1977-01-01

In the rat, infusion of a volume of isotonic saline equal to 2% of body weight resulted in an 82% increase in the delivery of filtrate out of the proximal tubule but little or, in some animals, no change in the urinary excretion of sodium. By contrast, further degrees of volume expansion resulted in lesser increases in the distal delivery of filtrate, but were associated with a marked increase in the urinary excretion of sodium. Sixty minutes following completion of volume expansion, while the animals were still in positive sodium balance, the urinary excretion of sodium decreased 52% compared to a decrease of only 24% in the distal delivery of filtrate. During the course of progressive volume expansion and during the recovery phase, there was a dissociation between alterations in sodium reabsorption in the proximal convoluted tubule and in the whole kidney. These studies indicate that although the proximal tubule is more sensitive to changes in the extracellular fluid volume, distal nephron sites are ultimately responsible both for the natriuresis of volume expansion and the relative antinatriuresis of the recovery periods.

PET/CT-guided treatment planning for paediatric cancer patients: a simulation study of proton and conventional photon therapy

PubMed Central

Brodin, N P; Björk-Eriksson, T; Birk Christensen, C; Kiil-Berthelsen, A; Aznar, M C; Hollensen, C; Markova, E; Munck af Rosenschöld, P

2015-01-01

Objective: To investigate the impact of including fluorine-18 fludeoxyglucose (18F-FDG) positron emission tomography (PET) scanning in the planning of paediatric radiotherapy (RT). Methods: Target volumes were first delineated without and subsequently re-delineated with access to 18F-FDG PET scan information, on duplicate CT sets. RT plans were generated for three-dimensional conformal photon RT (3DCRT) and intensity-modulated proton therapy (IMPT). The results were evaluated by comparison of target volumes, target dose coverage parameters, normal tissue complication probability (NTCP) and estimated risk of secondary cancer (SC). Results: Considerable deviations between CT- and PET/CT-guided target volumes were seen in 3 out of the 11 patients studied. However, averaging over the whole cohort, CT or PET/CT guidance introduced no significant difference in the shape or size of the target volumes, target dose coverage, irradiated volumes, estimated NTCP or SC risk, neither for IMPT nor 3DCRT. Conclusion: Our results imply that the inclusion of PET/CT scans in the RT planning process could have considerable impact for individual patients. There were no general trends of increasing or decreasing irradiated volumes, suggesting that the long-term morbidity of RT in childhood would on average remain largely unaffected. Advances in knowledge: 18F-FDG PET-based RT planning does not systematically change NTCP or SC risk for paediatric cancer patients compared with CT only. 3 out of 11 patients had a distinct change of target volumes when PET-guided planning was introduced. Dice and mismatch metrics are not sufficient to assess the consequences of target volume differences in the context of RT. PMID:25494657

The cost of implementation of the Clinical Laboratory Improvement Amendments of 1988--the example of pediatric office-based cholesterol screening.

PubMed

Tershakovec, A M; Brannon, S D; Bennett, M J; Shannon, B M

1995-08-01

To measure the additional costs of office-based laboratory testing due to the implementation of the Clinical Laboratory Improvement Amendments of 1988 (CLIA '88), using cholesterol screening for children as an example. Four- to ten-year-old children who received their well child care at one of seven participating pediatric practices were screened for hypercholesterolemia. The average number of analyses per day and days per month were derived from the volume of testing completed by the practices. Nurses and technicians time in the screening process were measured and personnel costs were calculated based on salary and fringe benefit rates. Costs of supplies, analyzing control samples, instrument calibration, and instrument depreciation were included. Costs estimates of screening were then completed. CLIA '88 implementation costs were derived from appropriate proficiency testing and laboratory inspection programs. In six practices completing a low volume of testing, 2807 children (5 to 6 children per week) were screened during the observation period, while 414 (about 25 children per week) were screened in one high-volume practice implementing universal screening over a 4-month period. For the six low-volume practices, the cost of screening was $10.60 per child. This decreased to $5.47 for the high-volume practice. Estimated costs of CLIA '88 implementation, including additional proficiency testing and laboratory inspection, added $3.20 per test for the low-volume practices, and $0.71 per test for the high-volume testing. Implementation of CLIA adds significantly to the cost of office-based chemistry laboratory screening. Despite these additional expenses, the cost of testing is still within a reasonable charge for laboratory testing, and is highly sensitive to the volume of tests completed.

Theoretical study of the partial molar volume change associated with the pressure-induced structural transition of ubiquitin

PubMed Central

Imai, Takashi; Ohyama, Shusaku; Kovalenko, Andriy; Hirata, Fumio

2007-01-01

The partial molar volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the volume of structural voids in the protein, which is partially canceled by the volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier. PMID:17660257

Theoretical study of the partial molar volume change associated with the pressure-induced structural transition of ubiquitin.

PubMed

Imai, Takashi; Ohyama, Shusaku; Kovalenko, Andriy; Hirata, Fumio

2007-09-01

The partial molar volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the volume of structural voids in the protein, which is partially canceled by the volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier.

Protoplast Volume:Water Potential Relationship and Bound Water Fraction in Spinach Leaves 1

PubMed Central

Santakumari, Mane; Berkowitz, Gerald A.

1989-01-01

Methods used to estimate the (nonosmotic) bound water fraction (BWF) (i.e. apoplast water) of spinach (Spinacia oleracea L.) leaves were evaluated. Studies using three different methods of pressure/volume (P/V) curve construction all resulted in a similar calculation of BWF; approximately 40%. The theoretically derived BWF, and the water potential (Ψw)/relative water content relationship established from P/V curves were used to establish the relationship between protoplast (i.e. symplast) volume and Ψw. Another method of establishing the protoplast volume/Ψw relationship in spinach leaves was compared with the results from P/V curve experiments. This second technique involved the vacuum infiltration of solutions at a range of osmotic potentials into discs cut from spinach leaves. These solutions contained radioactively labeled H2O and sorbitol. This dual label infiltration technique allowed for simultaneous measurement of the total and apoplast volumes in leaf tissue; the difference yielded the protoplast volume. The dual label infiltration experiments and the P/V curve constructions both showed that below −1 megapascals, protoplast volume decreases sharply with decreasing water potential; with 50% reduction in protoplast volume occurring at −1.8 megapascals leaf water potential. PMID:16666983

Does price efficiency increase with trading volume? Evidence of nonlinearity and power laws in ETFs

NASA Astrophysics Data System (ADS)

Caginalp, Gunduz; DeSantis, Mark

2017-02-01

Whether efficiency increases with increasing volume is an important issue that may illuminate trader strategies and distinguish between market theories. This relationship is tested using 124,236 daily observations comprising 68 large and liquid U.S. equity exchange traded funds (ETFs). ETFs have the advantage that efficiency can be measured in terms of the deviation between the trading price and the underlying net asset value that is reported each day. Our findings support the hypothesis that the relationship between volume and efficiency is nonlinear. Indeed, efficiency increases as volume increases from low to moderately high levels, but then decreases as volume increases further. The first part tends to support the idea that higher volume simply facilitates transactions and maintains efficiency, while the latter part, i.e., even higher volumes, supports the ansatz that increased volume is associated with increased speculation that ignores valuation and decreases efficiency. The results are consistent with the hypothesis that valuation is only part of the motivation for traders. Our methodology accounts for fund heterogeneity and contemporaneous correlations. Similar results are obtained when daily price volatility is introduced as an additional independent variable.

Universal behavior of the osmotically compressed cell and its analogy to the colloidal glass transition

PubMed Central

Zhou, E. H.; Trepat, X.; Park, C. Y.; Lenormand, G.; Oliver, M. N.; Mijailovich, S. M.; Hardin, C.; Weitz, D. A.; Butler, J. P.; Fredberg, J. J.

2009-01-01

Mechanical robustness of the cell under different modes of stress and deformation is essential to its survival and function. Under tension, mechanical rigidity is provided by the cytoskeletal network; with increasing stress, this network stiffens, providing increased resistance to deformation. However, a cell must also resist compression, which will inevitably occur whenever cell volume is decreased during such biologically important processes as anhydrobiosis and apoptosis. Under compression, individual filaments can buckle, thereby reducing the stiffness and weakening the cytoskeletal network. However, the intracellular space is crowded with macromolecules and organelles that can resist compression. A simple picture describing their behavior is that of colloidal particles; colloids exhibit a sharp increase in viscosity with increasing volume fraction, ultimately undergoing a glass transition and becoming a solid. We investigate the consequences of these 2 competing effects and show that as a cell is compressed by hyperosmotic stress it becomes progressively more rigid. Although this stiffening behavior depends somewhat on cell type, starting conditions, molecular motors, and cytoskeletal contributions, its dependence on solid volume fraction is exponential in every instance. This universal behavior suggests that compression-induced weakening of the network is overwhelmed by crowding-induced stiffening of the cytoplasm. We also show that compression dramatically slows intracellular relaxation processes. The increase in stiffness, combined with the slowing of relaxation processes, is reminiscent of a glass transition of colloidal suspensions, but only when comprised of deformable particles. Our work provides a means to probe the physical nature of the cytoplasm under compression, and leads to results that are universal across cell type. PMID:19520830

A study of the effectiveness and energy efficiency of ultrasonic emulsification.

PubMed

Li, Wu; Leong, Thomas S H; Ashokkumar, Muthupandian; Martin, Gregory J O

2017-12-20

Three essential experimental parameters in the ultrasonic emulsification process, namely sonication time, acoustic amplitude and processing volume, were individually investigated, theoretically and experimentally, and correlated to the emulsion droplet sizes produced. The results showed that with a decrease in droplet size, two kinetic regions can be separately correlated prior to reaching a steady state droplet size: a fast size reduction region and a steady state transition region. In the fast size reduction region, the power input and sonication time could be correlated to the volume-mean diameter by a power-law relationship, with separate power-law indices of -1.4 and -1.1, respectively. A proportional relationship was found between droplet size and processing volume. The effectiveness and energy efficiency of droplet size reduction was compared between ultrasound and high-pressure homogenisation (HPH) based on both the effective power delivered to the emulsion and the total electric power consumed. Sonication could produce emulsions across a broad range of sizes, while high-pressure homogenisation was able to produce emulsions at the smaller end of the range. For ultrasonication, the energy efficiency was higher at increased power inputs due to more effective droplet breakage at high ultrasound intensities. For HPH the consumed energy efficiency was improved by operating at higher pressures for fewer passes. At the laboratory scale, the ultrasound system required less electrical power than HPH to produce an emulsion of comparable droplet size. The energy efficiency of HPH is greatly improved at large scale, which may also be true for larger scale ultrasonic reactors.

Computational Quantification of the Cardiac Energy Consumption during Intra-Aortic Balloon Pumping Using a Cardiac Electromechanics Model

PubMed Central

Lim, Ki Moo; Lee, Jeong Sang; Gyeong, Min-Soo; Choi, Jae-Sung; Choi, Seong Wook

2013-01-01

To quantify the reduction in workload during intra-aortic balloon pump (IABP) therapy, indirect parameters are used, such as the mean arterial pressure during diastole, product of heart rate and peak systolic pressure, and pressure-volume area. Therefore, we investigated the cardiac energy consumption during IABP therapy using a cardiac electromechanics model. We incorporated an IABP function into a previously developed electromechanical model of the ventricle with a lumped model of the circulatory system and investigated the cardiac energy consumption at different IABP inflation volumes. When the IABP was used at inflation level 5, the cardiac output and stroke volume increased 11%, the ejection fraction increased 21%, the stroke work decreased 1%, the mean arterial pressure increased 10%, and the ATP consumption decreased 12%. These results show that although the ATP consumption is decreased significantly, stroke work is decreased only slightly, which indicates that the IABP helps the failed ventricle to pump blood efficiently. PMID:23341718

Computational quantification of the cardiac energy consumption during intra-aortic balloon pumping using a cardiac electromechanics model.

PubMed

Lim, Ki Moo; Lee, Jeong Sang; Gyeong, Min-Soo; Choi, Jae-Sung; Choi, Seong Wook; Shim, Eun Bo

2013-01-01

To quantify the reduction in workload during intra-aortic balloon pump (IABP) therapy, indirect parameters are used, such as the mean arterial pressure during diastole, product of heart rate and peak systolic pressure, and pressure-volume area. Therefore, we investigated the cardiac energy consumption during IABP therapy using a cardiac electromechanics model. We incorporated an IABP function into a previously developed electromechanical model of the ventricle with a lumped model of the circulatory system and investigated the cardiac energy consumption at different IABP inflation volumes. When the IABP was used at inflation level 5, the cardiac output and stroke volume increased 11%, the ejection fraction increased 21%, the stroke work decreased 1%, the mean arterial pressure increased 10%, and the ATP consumption decreased 12%. These results show that although the ATP consumption is decreased significantly, stroke work is decreased only slightly, which indicates that the IABP helps the failed ventricle to pump blood efficiently.

Changes in plasma volume during bed rest - Effects of menstrual cycle and estrogen administration

NASA Technical Reports Server (NTRS)

Fortney, S. M.; Beckett, W. S.; Carpenter, A. J.; Davis, J.; Drew, H.

1988-01-01

The effect of increased blood estrogen concentration, caused either during normal menstrual cycles or by exogenous administration of premarin, on the bed-rest (BR) induced decrease in plasma volume (PV) was investigated. In women who underwent duplicate 11-day BR without estrogen supplementation, the PV was found to decrease significantly, during the first 5 days of BR, to a lower level at which it remained for the rest of the BR period. In women who began BR in the periovulatory stage of the menstrual cycle, the loss of PV was delayed, while women who began BR during other stages of the cycle exhibited the usual trend of the PV decrease during the BR. In women who underwent a single 12-day BR period while taking premarin (1.25 mg/day), PV was found to decrease during the first 4-5 days of BR, but then returned toward the pre-BR level during the remainder of the BR, indicating that estrogens have a role in stabilizing body fluid volume.

Influence of Syringe Volume on Foam Stability in Sclerotherapy for Varicose Vein Treatment.

PubMed

Bai, Taoping; Jiang, Wentao; Fan, Yubo

2018-05-01

Despite the popularity of sclerotherapy for treating varicose veins, it still exhibits various problems, such as pulmonary embolism, deep-vein thrombosis, phlebitis, and visual disorders. To investigate syringe volume influence on foam stability, obtain the foam decay rule, and provide a reference for clinics. Five types of syringes are used to prepare foam at room temperature with various liquid-gas ratios. Foam decay process experiments were performed 5 times and recorded by video. The stability indices used include drainage time, half-life, bubble diameter, bubble surface density, and drainage rate. The 30 and 2-mL syringes, respectively, recorded the highest and lowest drainage speeds. Foam drainage time and half-life, differences varied between 15 and 70 seconds, and 20 and 100 seconds, respectively. Foam bubble diameters were distributed over 0.1 to 2.0 mm with roughly 200 to 700 bubbles per square centimeter. Increased syringe volume causes the bubble diameter to increase. Thus, foam dispersion increases and foam half-life decreases; hence, foam becomes unstable. It is, thus, better to use a small syringe several times to prepare foam in clinics using segmented injections.

[MRI for brain structure and function in patients with first-episode panic disorder].

PubMed

Zhang, Yan; Duan, Lian; Liao, Mei; Yang, Fan; Liu, Jun; Shan, Baoci; Li, Lingjiang

2011-12-01

To determine the brain function and structure in patinets with first-episode panic disorder (PD). All subjects (24 PD patients and 24 healthy subjects) received MRI scan and emotional counting Stroop task during the functional magnetic resonance imaging. Blood oxygenation level dependent functional magnetic resonance imaging and voxel-based morphometric technology were used to detect the gray matter volume. Compared with the healthy controls, left thalamus, left medial frontal gyrus, left anterior cingulate gyrus, left inferior frontal gyrus, left insula (panic-related words vs. neutral words) lacked activation in PD patients, but the over-activation were found in right brain stem, right occipital lobe/lingual gyrus in PD patients. Compared with the healthy controls, the gray matter volume in the PD patients significantly decreased in the left superior temporal gyrus, right medial frontal gyrus, left medial occipital gyrus, dorsomedial nucleus of left thalamus and right anterior cingulate gyrus. There was no significantly increased gray matter volume in any brain area in PD patients. PD patients have selective attentional bias in processing threatening information due to the depression and weakening of the frontal cingulated gyrus.

Pathophysiology and management of pediatric ascites.

PubMed

Sabri, Mahmoud; Saps, Miguel; Peters, John M

2003-06-01

Ascites accumulation is the product of a complex process involving hepatic, renal, systemic, hemodynamic, and neurohormonal factors. The main pathophysiologic theories of ascites formation include the "underfill," "overflow," and peripheral arterial vasodilation hypotheses. These theories are not necessarily mutually exclusive and are linked at some level by a common pathophysiologic thread: The body senses a decreased effective arterial blood volume, leading to stimulation of the sympathetic nervous system, arginine-vasopressin feedback loops, and the renin-angiotensin-aldosterone system. Cornerstones of ascites management include dietary sodium restriction and diuretics. Spironolactone is generally tried initially, with furosemide added if clinical response is suboptimal. More refractory patients require large-volume paracentesis (LVP) accompanied by volume expansion with albumin. Placement of a transjugular intrahepatic portosystemic shunt is reserved for individuals with compensated liver function who require very frequent sessions of LVP. Peritoneovenous shunts are not used in contemporary ascites management. Liver transplantation remains the definitive therapy for refractory ascites. Although treatment of ascites fails to improve survival, it benefits quality of life and limits the development of such complications as spontaneous bacterial peritonitis.

Aerosol Effects on Microphysical Processes, Storm Structure, and Cold Pool Strength in Simulated Supercell Thunderstorms from VORTEX-2 and VORTEX-SE

NASA Astrophysics Data System (ADS)

Guo, M.; Dawson, D. T., II; Baldwin, M. E.; Mansell, E. R.

2017-12-01

The cloud condensation nuclei (CCN) concentration has been found to strongly affect microphysical, dynamical and thermodynamical processes in supercells and other deep convective storms. Moreover, recent simulation studies have shown aerosols effects differ between higher- and lower-CAPE environments. Owing to the known sensitivity of severe storms to microphysical differences, studying the impact of aerosols supercell storms different environments is of clear societal importance. Tornadic environments in the southwastern U.S. are generally characterized by lower magnitudes CAPE and deeper tropospheric moisture than those in the Great Plains. These two regions were the focus of Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX)-2 and VORTEX-Southeast (SE) field campaigns, respectively. In our study, we simulate several cases from VORTEX-2 and -SE with the Advanced Regional Prediction System (ARPS) Model at 6 different CCN concentrations (100-3000 cm-3). We use NSSL 3-moment microphysics parameterization schemeto explicitly predict precipitation particle size distributions and microphysirocess rates. Overall, storms under the higher-CAPE VORTEX-2 environments are more sensitiveto the change of CCN than those under the lower-CAPE VORTEX-SE environments. Updraft volume decreases as CCN increases for the VORTEX-2 cases, whereas the opposite is true but with a much weaker trend for the VORTEX-SE cases. Moreover, the cold pool strength drops dramatically as CCN surpasses 1000 cm-3n the VORTEX-2 cases but barely changes for the VORTEX-SE cases. Through a microphysics budget analysis, we show the change of the importance of ice processes is key to the differing sensitivities. in the VORTEX-2 cases, deposition to ice nuclei, cloud drop freezing and rain drop freezing in the upper levels (5-11km) contribute more to latent heating since more rain and cloud drops are lifted above the freezing level due to stronger updrafts. For CCN concentration over 1000cm-3, the drops become too small for efficient accretion by graupel and hail, leading to considerable decrease of latent heating and thus updraft volume. Finally, the decrease in cold pool strength in the VORTEX-2 cases at higher CCN is due to the rapid decrease of graupel melting at lower levels (<2km).

Pulmonary venous flows reflect changes in left atrial hemodynamics during mitral balloon valvotomy.

PubMed

Yalçin, Fatih; El-Amrousy, Mahmoud; Müderrisoğlu, Haldun; Korkmaz, Mehmet; Flachskampf, Frank; Tuzcu, Murat; Garcia, Mario G; Thomas, James D

2002-01-01

Patients with mitral stenosis have usually blunted pulmonary venous (PV) flow, because of decreased mitral valve area and diastolic dysfunction. The authors compared changes in Doppler PV velocities by using transesophageal echocardiography (TEE) against hemodynamics parameters before and after mitral balloon valvotomy to observe relevance of PV velocities and endsystolic left atrial (LA) pressure-volume relationship. In 25 patients (aged 35 +/- 17 years) with mitral stenosis in sinus rhythm, changes in LA pressure and volumes were compared with PV velocities before and after valvotomy. Mitral valve area, mitral gradients, and deceleration time were obtained. Mitral valve area and mitral gradients changed from 1 +/- 0.2 cm2 and 14.6 +/- 5.4 mmHg to 1.9 +/- 0.3 cm2 and 6.3 +/- 1.7 mmHg, respectively (p<0.001). AR peak reverse flow velocity and AR duration decreased from 29 +/- 13 cm/s and 110 =/- 30 msec to 19 +/- 6 cm/s and 80 +/- 29 msec respectively (p<0.001). Transmitral Doppler E wave deceleration time decreased from 327 +/- 85 to 209 +/- 61 s and cardiac output increased from 4.2 +/- 1.0 to 5.2 +/- 1.1 L/minute (p<0.001). The changes in LA pressure were correlated with changes in S/D (r=0.57, p<0.05). The changes in endsystolic LA pressure-volume relationship were also correlated with changes in S/D (r=0.52, p<0.05). Endsystolic LA pressure-volume relationship decreased after mitral balloon valvotomy, as a result of a large decrease in pressure. PV systolic/diastolic (S/D) waves ratio reflects endsystolic LA pressure-volume relationship and may be used as another indicator of successful valvotomy.

Pulmonary venous flows reflect changes in left atrial hemodynamics during mitral balloon valvotomy

NASA Technical Reports Server (NTRS)

Yalcin, Fatih; El-Amrousy, Mahmoud; Muderrisoglu, Haldun; Korkmaz, Mehmet; Flachskampf, Frank; Tuzcu, Murat; Garcia, Mario G.; Thomas, James D.

2002-01-01

Patients with mitral stenosis have usually blunted pulmonary venous (PV) flow, because of decreased mitral valve area and diastolic dysfunction. The authors compared changes in Doppler PV velocities by using transesophageal echocardiography (TEE) against hemodynamics parameters before and after mitral balloon valvotomy to observe relevance of PV velocities and endsystolic left atrial (LA) pressure-volume relationship. In 25 patients (aged 35 +/- 17 years) with mitral stenosis in sinus rhythm, changes in LA pressure and volumes were compared with PV velocities before and after valvotomy. Mitral valve area, mitral gradients, and deceleration time were obtained. Mitral valve area and mitral gradients changed from 1 +/- 0.2 cm2 and 14.6 +/- 5.4 mmHg to 1.9 +/- 0.3 cm2 and 6.3 +/- 1.7 mmHg, respectively (p<0.001). AR peak reverse flow velocity and AR duration decreased from 29 +/- 13 cm/s and 110 =/- 30 msec to 19 +/- 6 cm/s and 80 +/- 29 msec respectively (p<0.001). Transmitral Doppler E wave deceleration time decreased from 327 +/- 85 to 209 +/- 61 s and cardiac output increased from 4.2 +/- 1.0 to 5.2 +/- 1.1 L/minute (p<0.001). The changes in LA pressure were correlated with changes in S/D (r=0.57, p<0.05). The changes in endsystolic LA pressure-volume relationship were also correlated with changes in S/D (r=0.52, p<0.05). Endsystolic LA pressure-volume relationship decreased after mitral balloon valvotomy, as a result of a large decrease in pressure. PV systolic/diastolic (S/D) waves ratio reflects endsystolic LA pressure-volume relationship and may be used as another indicator of successful valvotomy.

The overloaded right heart and ventricular interdependence.

PubMed

Naeije, Robert; Badagliacca, Roberto

2017-10-01

The right and the left ventricle are interdependent as both structures are nested within the pericardium, have the septum in common and are encircled with common myocardial fibres. Therefore, right ventricular volume or pressure overloading affects left ventricular function, and this in turn may affect the right ventricle. In normal subjects at rest, right ventricular function has negligible interaction with left ventricular function. However, the right ventricle contributes significantly to the normal cardiac output response to exercise. In patients with right ventricular volume overload without pulmonary hypertension, left ventricular diastolic compliance is decreased and ejection fraction depressed but without intrinsic alteration in contractility. In patients with right ventricular pressure overload, left ventricular compliance is decreased with initial preservation of left ventricular ejection fraction, but with eventual left ventricular atrophic remodelling and altered systolic function. Breathing affects ventricular interdependence, in healthy subjects during exercise and in patients with lung diseases and altered respiratory system mechanics. Inspiration increases right ventricular volumes and decreases left ventricular volumes. Expiration decreases both right and left ventricular volumes. The presence of an intact pericardium enhances ventricular diastolic interdependence but has negligible effect on ventricular systolic interdependence. On the other hand, systolic interdependence is enhanced by a stiff right ventricular free wall, and decreased by a stiff septum. Recent imaging studies have shown that both diastolic and systolic ventricular interactions are negatively affected by right ventricular regional inhomogeneity and prolongation of contraction, which occur along with an increase in pulmonary artery pressure. The clinical relevance of these observations is being explored. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Pressure-dependent changes in haematocrit and plasma volume during anaesthesia, a randomised clinical trial.

PubMed

Damén, T; Reinsfelt, B; Redfors, B; Nygren, A

2016-05-01

Induction of general anaesthesia has been shown to cause haemodilution and an increase in plasma volume. The aim of this study was to evaluate whether prevention of hypotension during anaesthesia induction could avoid haemodilution. Twenty-four cardiac surgery patients, 66 ± 10 years, were randomised to receive either norepinephrine in a dose needed to maintain mean arterial blood pressure (MAP) at pre-anaesthesia levels after induction or to a control group that received vasopressor if MAP decreased below 60 mmHg. No fluids were infused. Changes in plasma volume were calculated with standard formula: 100 × (Hct(pre)/Hct(post) - 1)/(1 - Hct(pre)). Arterial blood gas was analysed every 10 minutes and non-invasive continuous haemoglobin (SpHb) was continuously measured. Pre-anaesthesia MAP was 98 ± 7 mmHg. Ten minutes after anaesthesia induction, the haematocrit decreased by 5.0 ± 2.5% in the control group compared with 1.2 ± 1.4% in the intervention group, which corresponds to increases in plasma volume by 310 ml and 85 ml respectively. MAP decreased to 69 ± 15 mmHg compared to 92 ± 10 mmHg in the intervention group. The difference maintained throughout the 70 min intervention period. The change in haemoglobin level measured by blood gas analysis could not be detected by SpHb measurement. The mean bias between the SpHb and blood gas haemoglobin was 15 g/l. During anaesthesia induction, haematocrit decreases and plasma volume increases early and parallel to a decrease in blood pressure. This autotransfusion is blunted when blood pressure is maintained at pre-induction levels with norepinephrine. © 2016 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Resident operative experience in general surgery, plastic surgery, and urology 5 years after implementation of the ACGME duty hour policy.

PubMed

Simien, Christopher; Holt, Kathleen D; Richter, Thomas H; Whalen, Thomas V; Coburn, Michael; Havlik, Robert J; Miller, Rebecca S

2010-08-01

Resident duty hour restrictions were implemented in 2002-2003. This study examines changes in resident surgical experience since these restrictions were put into place. Operative log data for 3 specialties were examined: general surgery, urology, and plastic surgery. The academic year immediately preceding the duty hour restrictions, 2002-2003, was used as a baseline for comparison to subsequent academic years. Operative log data for graduating residents through 2007-2008 were the primary focus of the analysis. Examination of associated variables that may moderate the relationship between fewer duty hours and surgical volume was also included. Plastic surgery showed no changes in operative volume following duty hour restrictions. Operative volume increased in urology programs. General surgery showed a decrease in volume in some operative categories but an increase in others. Specifically the procedures in vascular, plastic, and thoracic areas showed a consistent decrease. There was no increase in the percentage of programs' graduates falling below minimum requirements. Procedures in pancreas, endocrine, and laparoscopic areas demonstrated an increase in volume. Graduates in larger surgical programs performed fewer procedures than graduates in smaller programs; this was not the case for urology or plastic surgery programs. The reduction of duty hours has not resulted in an across the board decrease in operative volume. Factors other than duty hour reforms may be responsible for some of the observed findings.

Atmospheric pressure plasma processing of polymeric materials utilizing close proximity indirect exposure

DOEpatents

Paulauskas, Felix L.; Bonds, Truman

2016-09-20

A plasma treatment method that includes providing treatment chamber including an intermediate heating volume and an interior treatment volume. The interior treatment volume contains an electrode assembly for generating a plasma and the intermediate heating volume heats the interior treatment volume. A work piece is traversed through the treatment chamber. A process gas is introduced to the interior treatment volume of the treatment chamber. A plasma is formed with the electrode assembly from the process gas, wherein a reactive species of the plasma is accelerated towards the fiber tow by flow vortices produced in the interior treatment volume by the electrode assembly.

First-time imaging of effects of inspired oxygen concentration on regional lung volumes and breathing pattern during hypergravity.

PubMed

Borges, João Batista; Hedenstierna, Göran; Bergman, Jakob S; Amato, Marcelo B P; Avenel, Jacques; Montmerle-Borgdorff, Stéphanie

2015-02-01

Aeroatelectasis can develop in aircrew flying the latest generation high-performance aircraft. Causes alleged are relative hyperoxia, increased gravity in the head-to-foot direction (+Gz), and compression of legs and stomach by anti-G trousers (AGT). We aimed to assess, in real time, the effects of hyperoxia, +Gz accelerations and AGT inflation on changes in regional lung volumes and breathing pattern evaluated in an axial plane by electrical impedance tomography (EIT). The protocol mimicked a routine peacetime flight in combat aircraft. Eight subjects wearing AGT were studied in a human centrifuge during 1 h 15 min exposure of +1 to +3.5Gz. They performed this sequence three times, breathing AIR, 44.5 % O2 or 100 % O2. Continuous recording of functional EIT enabled uninterrupted assessment of regional lung volumes at the 5th intercostal level. Breathing pattern was also monitored. EIT data showed that +3.5Gz, compared with any moment without hypergravity, caused an abrupt decrease in regional tidal volume (VT) and regional end-expiratory lung volume (EELV) measured in the EIT slice, independently of inspired oxygen concentration. Breathing AIR or 44.5 % O2, sub-regional EELV measured in the EIT slice decreased similarly in dorsal and ventral regions, but sub-regional VT measured in the EIT slice decreased significantly more dorsally than ventrally. Breathing 100 % O2, EELV and VT decreased similarly in both regions. Inspired tidal volume increased in hyperoxia, whereas breathing frequency increased in hypergravity and hyperoxia. Our findings suggest that hypergravity and AGT inflation cause airway closure and air trapping in gravity-dependent lung regions, facilitating absorption atelectasis formation, in particular during hyperoxia.

The impact of maternal plasma volume expansion and antihypertensive treatment with intravenous dihydralazine on fetal and maternal hemodynamics during pre-eclampsia: a clinical, echo-Doppler and viscometric study.

PubMed

Boito, S M E; Struijk, P C; Pop, G A M; Visser, W; Steegers, E A P; Wladimiroff, J W

2004-04-01

To establish the effects of plasma volume expansion (PVE) followed by intravenous dihydralazine (DH) administration on maternal whole blood viscosity (WBV) and hematocrit, uteroplacental and fetoplacental downstream impedance and umbilical venous (UV) volume flow in pre-eclampsia. In 13 pre-eclamptic women maternal and fetal hemodynamics were established by means of combined measurement of maternal arterial blood pressure (BP), WBV, hematocrit and uterine artery (UtA) resistance index (RI) in addition to umbilical artery (UA) pulsatility index (PI) and UV volume flow obtained from UV vessel area and UV time-averaged flow velocity. In each woman all parameters were measured four times at baseline, after PVE, after DH and 24 h after the start of treatment. Maternal diastolic BP, hematocrit and WBV display a significant reduction after PVE. In the fetus UA PI decreases significantly whereas a significant increase in UV cross-sectional area was detected. After maternal DH administration, arterial systolic and diastolic BP and UA PI show a significant decrease compared with the measurements following PVE. At 24 h, only maternal systolic and diastolic BP display a significant further decrease. No significant changes were established for the UtA RI, UV time-averaged velocity and UV volume flow during the entire study period. During pre-eclampsia, maternal PVE followed by DH administration results in a significant reduction in maternal diastolic BP, maternal hematocrit and WBV. Maternal PVE is associated with a significant increase in UV cross-sectional area and a non-significant rise of 11% in UV volume flow. Maternal DH administration does not result in any change in UV cross-sectional area. However, UA PI decreases significantly after both PVE and DH treatment. Copyright 2004 ISUOG.

Changes in the temperature-dependent specific volume of supported polystyrene films with film thickness.

PubMed

Huang, Xinru; Roth, Connie B

2016-06-21

Recent studies have measured or predicted thickness-dependent shifts in density or specific volume of polymer films as a possible means of understanding changes in the glass transition temperature Tg(h) with decreasing film thickness with some experimental works claiming unrealistically large (25%-30%) increases in film density with decreasing thickness. Here we use ellipsometry to measure the temperature-dependent index of refraction of polystyrene (PS) films supported on silicon and investigate the validity of the commonly used Lorentz-Lorenz equation for inferring changes in density or specific volume from very thin films. We find that the density (specific volume) of these supported PS films does not vary by more than ±0.4% of the bulk value for film thicknesses above 30 nm, and that the small variations we do observe are uncorrelated with any free volume explanation for the Tg(h) decrease exhibited by these films. We conclude that the derivation of the Lorentz-Lorenz equation becomes invalid for very thin films as the film thickness approaches ∼20 nm, and that reports of large density changes greater than ±1% of bulk for films thinner than this likely suffer from breakdown in the validity of this equation or in the difficulties associated with accurately measuring the index of refraction of such thin films. For larger film thicknesses, we do observed small variations in the effective specific volume of the films of 0.4 ± 0.2%, outside of our experimental error. These shifts occur simultaneously in both the liquid and glassy regimes uniformly together starting at film thicknesses less than ∼120 nm but appear to be uncorrelated with Tg(h) decreases; possible causes for these variations are discussed.

Association of Changes in Abdominal Fat and Cardiovascular Risk Factors

PubMed Central

Lee, Jane J.; Pedley, Alison; Hoffmann, Udo; Massaro, Joseph M.; Fox, Caroline S.

2017-01-01

BACKGROUND Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) are associated with adverse cardiometabolic risk profiles. OBJECTIVES This study explored the degree to which changes in abdominal fat quantity and quality are associated with changes in cardiovascular disease (CVD) risk factors. METHODS Study participants (n = 1,106; 44.1% women; mean baseline age 45.1 years) were drawn from the Framingham Heart Study Third Generation cohort who participated in the computed tomography (CT) substudy Exams 1 and 2. Participants were followed for 6.1 years on average. Abdominal adipose tissue volume in cm3 and attenuation in Hounsfield units (HU) were determined by CT-acquired abdominal scans. RESULTS The mean fat volume change was an increase of 602 cm3 for SAT and an increase of 703 cm3 for VAT; the mean fat attenuation change was a decrease of 5.5HU for SAT and an increase of 0.07 HU for VAT. An increase in fat volume and decrease in fat attenuation were associated with adverse changes in CVD risk factors. An additional 500 cm3 increase in fat volume was associated with incident hypertension (odds ratio [OR]: 1.21 for SAT; OR: 1.30 for VAT), hypertriglyceridemia (OR: 1.15 for SAT; OR: 1.56 for VAT), and metabolic syndrome (OR: 1.43 for SAT; OR: 1.82 for VAT; all p < 0.05). Similar trends were observed for each additional 5 HU decrease in abdominal adipose tissue attenuation. Most associations remained significant even after further accounting for body mass index change, waist circumference change, or respective abdominal adipose tissue volumes. CONCLUSIONS Increasing accumulation of fat quantity and decreasing fat attenuation are associated with worsening of CVD risk factors beyond the associations with generalized adiposity, central adiposity, or respective adipose tissue volumes. PMID:27687192

The effect of vitamin C on plasma volume in the early stage of sepsis in the rat.

PubMed

Bark, Björn P; Grände, Per-Olof

2014-12-01

Previous experimental studies have shown that vitamin C has several beneficial effects in sepsis and burns, such as decreased tissue oedema, improved endothelial barrier function and decreased transcapillary leakage of plasma markers. It has still not been investigated, though, if vitamin C has any impact specifically on plasma volume. The present study aims at testing the hypothesis that vitamin C decreases plasma volume loss in sepsis. Anaesthetized male adult Sprague-Dawley rats were used in this prospective randomized study. All experiments were carried out at a university hospital laboratory. Sepsis was induced by caecal ligation and incision. After 3 h, vitamin C was given either as a bolus dose (66 mg/kg) followed by a continuous infusion (33 mg/kg/h) (n = 9), or as a single bolus dose (200 mg/kg) (n = 9). A sham group (n = 9) underwent the same surgical procedure, but no vitamin C was given. Plasma volume was measured ((125)I-dilution technique) at baseline, at 3 h after end of initiation of sepsis and at the end of the experiment 3 h later. Arterial blood samples for analyses of electrolytes, blood gases, haematocrit and lactate were taken at the same time points. There were no significant differences in plasma volumes or the physiological parameters analysed between any of the three groups at any time point. There was a significantly larger urine production in the single bolus dose group (200 mg/kg) compared to the sham group. Vitamin C treatment did not decrease the loss of plasma volume in the septic rat. The diuretic effect of vitamin C was in accordance with previous studies.

Pushing quantitation limits in micro UHPLC-MS/MS analysis of steroid hormones by sample dilution using high volume injection.

PubMed

Márta, Zoltán; Bobály, Balázs; Fekete, Jenő; Magda, Balázs; Imre, Tímea; Mészáros, Katalin Viola; Szabó, Pál Tamás

2016-09-10

Ultratrace analysis of sample components requires excellent analytical performance in terms of limits of quantitation (LoQ). Micro UHPLC coupling with sensitive tandem mass spectrometry provides state of the art solutions for such analytical problems. Decreased column volume in micro LC limits the injectable sample volume. However, if analyte concentration is extremely low, it might be necessary to inject high sample volumes. This is particularly critical for strong sample solvents and weakly retained analytes, which are often the case when preparing biological samples (protein precipitation, sample extraction, etc.). In that case, high injection volumes may cause band broadening, peak distortion or even elution in dead volume. In this study, we evaluated possibilities of high volume injection onto microbore RP-LC columns, when sample solvent is diluted. The presented micro RP-LC-MS/MS method was optimized for the analysis of steroid hormones from human plasma after protein precipitation with organic solvents. A proper sample dilution procedure helps to increase the injection volume without compromising peak shapes. Finally, due to increased injection volume, the limit of quantitation can be decreased by a factor of 2-5, depending on the analytes and the experimental conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

Detector Dewar cooler assemblies trade-off with equipment needs: a key issue for cost reduction

NASA Astrophysics Data System (ADS)

Chatard, Jean-Pierre

1996-06-01

Low cost equipment is the universal motto with the decrease in military budgets. A large panoply exists to solve partially this problem, such as simplification of the process, industrialization and the use of a collective manufacturing concept; but this is not enough. In the field of IRFPA using Mercury Cadmium Telluride (MCT), Sofradir has spent a lot of time in order to develop a very simple process to ensure producibility which has been totally demonstrated today. The production of more than 25 complex IRFPA per month has also allowed us to industrialize the process. A key factor is quantities. Today the only solution to increase quantities is to standardize detectors but in the field of IRFPA it is not so easy because each imaging system is specific. One solution to decrease the cost is to obtain the best trade-off between the application and the technology. As an example, people focus on indium antimonide staring array detectors today as they consider them as less expensive than other cooled infrared detector technologies. This is just because people focus on the FPA only, not on the global cost of the equipment. It will be demonstrated in this paper that MCT is a material so flexible that it is possible to obtain InSb detector performance at a higher temperature which allows decreased cost, volume and weight of the infrared equipment.

Decreases in Human Semen Quality with Age Among Healthy Men

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eskenazi, B.; Wyrobek, A.J.; Kidd, S.A.

The objective of this report is to characterize the associations between age and semen quality among healthy active men after controlling for identified covariates. Ninety-seven healthy, nonsmoking men between 22 and 80 years without known fertility problems who worked for or retired from a large research laboratory. There was a gradual decrease in all semen parameters from 22-80 years of age. After adjusting for covariates, volume decreased 0.03 ml per year (p = 0.001); sperm concentration decreased 2.5% per year (p = 0.005); total count decreased 3.6% per year of age (p < 0.001); motility decreased 0.7% per year (Pmore » < 0.001); progressive motility decreased 3.1% per year (p < 0.001); and total progressively motile sperm decreased 4.8% per year (p < 0.001). In a group of healthy active men, semen volume, sperm concentration, total sperm count, and sperm motility decrease continuously between 22-80 years of age, with no evidence of a threshold.« less

Bladder filling variation during conformal radiotherapy for rectal cancer

NASA Astrophysics Data System (ADS)

Sithamparam, S.; Ahmad, R.; Sabarudin, A.; Othman, Z.; Ismail, M.

2017-05-01

Conformal radiotherapy for rectal cancer is associated with small bowel toxicity mainly diarrhea. Treating patients with a full bladder is one of the practical solutions to reduce small bowel toxicity. Previous studies on prostate and cervix cancer patients revealed that maintaining consistent bladder volume throughout radiotherapy treatment is challenging. The aim of this study was to measure bladder volume variation throughout radiotherapy treatment. This study also measured the association between bladder volume changes and diarrhea. Twenty two rectal cancer patients were recruited prospectively. Patients were planned for treatment with full bladder following departmental bladder filling protocol and the planning bladder volume was measured during CT-simulation. During radiotherapy, the bladder volume was measured weekly using cone-beam computed tomography (CBCT) and compared to planning bladder volume. Incidence and severity of diarrhea were recorded during the weekly patient review. There was a negative time trend for bladder volume throughout five weeks treatment. The mean bladder volume decreased 18 % from 123 mL (SD 54 mL) during CT-simulation to 101 mL (SD 71 mL) on the 5th week of radiotherapy, but the decrease is not statistically significant. However, there was a large variation of bladder volume within each patient during treatment. This study showed an association between changes of bladder volume and diarrhea (P = 0.045). In conclusion bladder volume reduced throughout radiotherapy treatment for conformal radiotherapy for rectal cancer and there was a large variation of bladder volume within patients.

Structural MRI research in patients with nasopharyngeal carcinoma following radiotherapy: A DTI and VBM study.

PubMed

Leng, Xi; Fang, Peng; Lin, Huan; An, Jie; Tan, Xin; Zhang, Chi; Wu, Donglin; Shen, Wen; Qiu, Shijun

2017-11-01

The aim of the present study was to investigate the microstructural characteristics of the brain lobes following radiotherapy (RT) for patients with nasopharyngeal carcinoma (NPC) at distinct times. Diffusion tensor imaging (DTI) and 3D-T1-weighted imaging was performed in 70 age- and sex-matched subjects, 24 of whom were pre-treatment patients. The patients were divided into three groups, according to the time following completion of RT. Fractional anisotropy (FA) and gray matter (GM) volume were determined. The DTI data were analyzed using tract-based spatial statistics and the GM volume was analyzed using voxel-based morphometry (VBM). Compared with the pre-RT group, the mean FA values in the left parietal lobe white matter (WM) and right cerebellum decreased significantly in the post-RT 0-6 month group (P<0.05). In addition, the mean FA values in the right parietal lobe WM decreased significantly in the post-RT 6-12 month group (P<0.05), compared with the pre-RT group. The FA level in the right temporal lobe remained significantly decreased, compared with that in the pre-RT group (P<0.05) for 1 year after RT. Furthermore, compared with pre-RT group, the GM volume in the bilateral frontal lobe, right occipital lobe, left parietal lobe, right temporal lobe and left cerebellum decreased significantly in the post-RT 0-6 month group (P<0.05), and in the bilateral temporal lobe, parietal lobe, right frontal lobe and left cerebellum, the GM volume decreased significantly in the post-RT 6-12 month group (P<0.05). The GM volume in the right temporal lobe, bilateral frontal lobe and bilateral cerebellum remained significantly decreased compared with that in the pre-RT group (P<0.05) for 1 year after RT. A combination of DTI and VBM may be used to determine radiation-induced brain injury in patients treated for NPC.

The size-isotopic evolution connection among layered mafic instrusions: Clues from a Sr-Nd isotopic study of a small complex

NASA Astrophysics Data System (ADS)

Poitrasson, Franck; Pin, Christian; Duthou, Jean-Louis; Platevoet, Bernard

1994-05-01

Several theoretical and experimental works have focused on the processes occuring in continental mafic magma chambers. In contrast, systematic isotopic studies of natural remnants of these latter remain scarce, although they can give fundamental constraints for theoretical studies. This is especially true if different layered complex with contrasting characteristics (e.g., different size) are compared. For this reason, we present the results of a Sr-Nd isotopic profile across a small layered mafic intrusion of Permian age exposed near Fozzano (SW Corsica). In the main zone of the layered section, decreasing Sr-87/Sr(sub i)-86 and increasing Nd-143/Nd(sub i)-144 are observed from less evolved (bottom) to more evolved (top) rocks. This peculiar pattern precludes assimilation and fractional crystallization (AFC) as a dominant mechanism in the petrogenesis of this body. Instead, we interpret this trend as reflecting the dilution of an early stage contaminated magma by several reinjections of fresh basalt in the chamber. In agreement with mineralogical and structural data, every cyclic unit is interpreted as a new magmatic input. On the basis of rough refill and fractional crystallization (RFC) calculations, the average volume for each reinjection is estimated to have been about 0.04 cu km. The cumulative volume of these injections would amount to about 75% of the total volume of the layered complex. This implies that reinjections were accompanied by an important increase of the volume of the chamber or by magma withdrawal by surface eruptions. The RFC mechanism documented within this small layered body constrasts with the isotopic pattern observed between several intrusions at the regional scale in SW Corsica, and within large continental mafic magma chambers elsewhere. In these cases the isotopic evolution is dominated by AFC processes, and there is no clear isotopic evidence for reinjections, unless major influx of fresh magma occurred. It is suggested that there is a close relationship between the assimilation rate and the magma chamber volume. Small magma chambers are quickly isolated from their country rocks and better preserve the subtle isotopic signature of reinjection processes.

Viscoelastic properties, gelation behavior and percolation theory model for the temperature induced forming (TIF) ceramic slurries

NASA Astrophysics Data System (ADS)

Yang, Yunpeng

Controlled ceramic processing is required to produce ceramic parts with few strength-limiting defects and the economic forming of near net shape components. Temperature induced forming (TIF) is a novel ceramic forming process that uses colloidal processing to form ceramic green bodies by physical gelation. The dissertation research shows that TIF alumina suspensions (>40vol%) can be successfully fabricated by using 0.4wt% of ammonium citrate powder and <0.1wt% poly (acrylic acid) (PAA). It is found that increasing the volume fraction of alumina or the molecular weight of polymer will increase the shear viscosity and shear modulus. Larger molecular weight PAA tends to decrease the volume fraction gelation threshold of the alumina suspensions. The author is the first in this field to utilize the continuous percolation theory to interpret the evolution of the storage modulus with temperature for the TIF alumina suspensions. A model that relates the storage modulus with temperature and the volume fraction of solids is proposed. Calculated results using this percolation model show that the storage modulus of the suspensions can be affected by the volume fraction of solids, temperature, volume fraction gelation threshold and the percolation nature. The parameters in this model have been derived from the experimental data. The calculated results fit the measured data well. For the PAA-free TIF alumina suspensions, it is found that the ionization reaction of the magnesium citrate, which is induced by the pH or temperature of the suspensions, controls the flocculation of the suspensions. The percolation theory model was successfully applied to this type of suspension. Compared with the PAA addition TIF suspensions, these suspensions reflect a higher degree of percolation nature, as indicated by a larger value of percolation exponent. These results show that the percolation model proposed in this dissertation can be used to predict the gelation degree of the TIF suspensions. Complex-shape engineering ceramic parts have been successfully fabricated by direct casting using the TIF alumina suspensions, which has a relative density of ˜65%. The sintered sample at 1550°C for 2h is translucent and has a uniform grain size.

Cardiovascular consequences of bed rest: effect on maximal oxygen uptake

NASA Technical Reports Server (NTRS)

Convertino, V. A.

1997-01-01

Maximal oxygen uptake (VO2max) is reduced in healthy individuals confined to bed rest, suggesting it is independent of any disease state. The magnitude of reduction in VO2max is dependent on duration of bed rest and the initial level of aerobic fitness (VO2max), but it appears to be independent of age or gender. Bed rest induces an elevated maximal heart rate which, in turn, is associated with decreased cardiac vagal tone, increased sympathetic catecholamine secretion, and greater cardiac beta-receptor sensitivity. Despite the elevation in heart rate, VO2max is reduced primarily from decreased maximal stroke volume and cardiac output. An elevated ejection fraction during exercise following bed rest suggests that the lower stroke volume is not caused by ventricular dysfunction but is primarily the result of decreased venous return associated with lower circulating blood volume, reduced central venous pressure, and higher venous compliance in the lower extremities. VO2max, stroke volume, and cardiac output are further compromised by exercise in the upright posture. The contribution of hypovolemia to reduced cardiac output during exercise following bed rest is supported by the close relationship between the relative magnitude (% delta) and time course of change in blood volume and VO2max during bed rest, and also by the fact that retention of plasma volume is associated with maintenance of VO2max after bed rest. Arteriovenous oxygen difference during maximal exercise is not altered by bed rest, suggesting that peripheral mechanisms may not contribute significantly to the decreased VO2max. However reduction in baseline and maximal muscle blood flow, red blood cell volume, and capillarization in working muscles represent peripheral mechanisms that may contribute to limited oxygen delivery and, subsequently, lowered VO2max. Thus, alterations in cardiac and vascular functions induced by prolonged confinement to bed rest contribute to diminution of maximal oxygen uptake and reserve capacity to perform physical work.

Unregulated proliferation of trauma centers undermines cost efficiency of population-based injury control.

PubMed

Tepas, Joseph J; Kerwin, Andrew J; Ra, Jin Hee

2014-03-01

We evaluated the impact on coverage and regional cost of trauma care produced by the activation of a Level II center with no preceding needs analysis in an established trauma region with a Level I center. Patient deidentified trauma registry data for years 2010, 2011, and 2012 were analyzed to assess the effect on trauma service volume during a period at the midpoint of which the Level II center was activated. Trends for each year were evaluated by patient volume, mechanism, resource use as reflected in a transfer to the intensive care unit (ICU) and ICU stay, patient severity as defined by Injury Severity Score (ISS), and patient injury profile determined by mean body region Abbreviated Injury Scale (AIS) score. Between 2010 and 2011, during which the Level II opened, overall volume at the Level I center dropped by 3.7%, and blunt volume remained unchanged. From 2011 to 2012, overall Level I volume dropped by 9.4%, and blunt injury fell by 14%. Proportions requiring immediate operating room or ICU care did not change. ISS distribution at the Level I center across the years was similar. Head, chest, and abdominal injuries, as assessed by AIS body region, increased slightly in severity and decreased in volume by 25%, 17%, and 18%, respectively. For 2012, the new center publically reported treating 1,100 patients, which, in concert with the Level I decrease, translates to increasing regional trauma center access by 25% while increasing expense of necessary core personnel by 217%. Addition of a second trauma center in a stable region, in which injury incidence was actually decreasing, doubled the cost of personnel, one of the most expensive components of the trauma system and decreased the volume of injuries necessary for training and education. Trauma system expansion must be based on needs assessment, which assures system survival and controls societal cost. Economic & value-based evaluation, level III.

Assessing the impact of the extended-release/long-acting opioid an-algesics risk evaluation and mitigation strategies on opioid prescrip-tion volume.

PubMed

Divino, Victoria; Cepeda, M Soledad; Coplan, Paul; Maziere, Jean-Yves; Yuan, Yingli; Wade, Rolin L

The Food and Drug Administration approved the extended-release/long-acting (ER/LA) opioid analgesics risk evaluation and mitigation strategies (REMS) in July 2012 to educate healthcare providers and patients about safe and appropriate opioid analgesic use. The authors evaluated the impact of the REMS on ER/LA opioid analgesic utilization, overall and stratified by patient characteristics and prescriber type associated with greater expected need for analgesia. Retrospective repeated cross-sectional study. QuintilesIMS's National Prescription Audit™ and LifeLink™ patient-level longitudinal prescription databases measured prescription volumes, projected to national estimates. Changes were assessed in ER/LA opioid analgesic prescriptions dispensed from the 2-year pre-REMS implementation (July 2010 to June 2012) to the 18-month post-REMS implementation (July 2013 to December 2014) periods (with 12-month transitional implementation period in between). Average quarterly ER/LA opioid prescription volume significantly decreased by 4.3 percent from Preimple-mentation to the Active Period (5.58 vs 5.34 million, p < 0.001). Differences in prescription volume change were observed between age, gender, and payer types. Prescription volume either significantly decreased or remained stable from Preimplementation to the Active Period among most provider specialties evaluated. The largest volume decreases were observed for dentists (-48.5 percent) and emergency medicine specialists (-25.5 percent) (both p < 0.001). The largest increases were observed for nurse practitioners (+33.7 percent) and physician assistants (+31.2 percent; both p < 0.001), whose overall prescribing of nonopioid medications also increased. A significant decrease in dispensed ER/LA opioid prescriptions was observed following REMS implementation compared to Preimplementation. The impact on volume varied by patient characteristics and prescriber specialty. The REMS program, in conjunction with other healthcare policies and initiatives, likely influenced these observations.

Pituitary gland shrinkage in bipolar disorder: The role of gender.

PubMed

Delvecchio, Giuseppe; Mandolini, Gian Mario; Perlini, Cinzia; Barillari, Marco; Marinelli, Veronica; Ruggeri, Mirella; Altamura, A Carlo; Bellani, Marcella; Brambilla, Paolo

2018-04-01

Hyperactivity of the Hypothalamic-Pituitary-Adrenal Axis (HPAA) has been consistently reported in mood disorders. However, only few studies investigated the Pituitary gland (PG) in Bipolar Disorder (BD) and the results are so far contrasting. Therefore, the aim of this study is to explore the integrity of the PG as well as the role of gender and the impact of clinical measurements on this structure in a sample of BD patients compared to healthy controls (HC). 34 BD patients and 41 HC underwent a 1.5 T MRI scan. PG volumes were manually traced for all subjects. Psychiatric symptoms were assessed by means of the Brief Psychiatry Rating Scale, the Hamilton Depression Rating Scale and the Bech Rafaelsen Mania Rating Scale. We found decreased PG volumes in BD patients compared to HC (F = 24.9, p < 0.001). Interestingly, after dividing the sample by gender, a significant PG volume decrease was detected only in female BD patients compared to female HC (F = 9.1, p < 0.001), but not in male BD compared to male HC (F = -0.12, p = 0.074). No significant correlations were observed between PG volumes and clinical variables. Our findings suggest that BD patients have decreased PG volumes, probably due to the long-term hyperactivity of the HPAA and to the consequent strengthening of the negative feedback control towards the PG volume itself. This alteration was particularly evident in females, suggesting a role of gender in affecting PG volumes in BD. Finally, the absence of significant correlations between PG volumes and clinical variables further supports that PG disruption is a trait feature of BD, being independent of symptoms severity and duration of treatment. Copyright © 2018 Elsevier Inc. All rights reserved.

Boron Nitride Nanoribbons from Exfoliation of Boron Nitride Nanotubes

NASA Technical Reports Server (NTRS)

Hung, Ching-Cheh; Hurst, Janet; Santiago, Diana

2017-01-01

Two types of boron nitride nanotubes (BNNTs) were exfoliated into boron nitride nanoribbons (BNNR), which were identified using transmission electron microscopy: (1) commercial BNNTs with thin tube walls and small diameters. Tube unzipping was indicated by a large decrease of the sample's surface area and volume for pores less than 2 nm in diameter. (2) BNNTs with large diameters and thick walls synthesized at NASA Glenn Research Center. Here, tube unraveling was indicated by a large increase in external surface area and pore volume. For both, the exfoliation process was similar to the previous reported method to exfoliate commercial hexagonal boron nitride (hBN): Mixtures of BNNT, FeCl3, and NaF (or KF) were sequentially treated in 250 to 350 C nitrogen for intercalation, 500 to 750 C air for exfoliation, and finally HCl for purification. Property changes of the nanosized boron nitride throughout this process were also similar to the previously observed changes of commercial hBN during the exfoliation process: Both crystal structure (x-ray diffraction data) and chemical properties (Fourier-transform infrared spectroscopy data) of the original reactant changed after intercalation and exfoliation, but most (not all) of these changes revert back to those of the reactant once the final, purified products are obtained.

Enhanced removal of arsenic from a highly laden industrial effluent using a combined coprecipitation/nano-adsorption process.

PubMed

Jiang, Yingnan; Hua, Ming; Wu, Bian; Ma, Hongrui; Pan, Bingcai; Zhang, Quanxing

2014-05-01

Effective arsenic removal from highly laden industrial wastewater is an important but challenging task. Here, a combined coprecipitation/nano-adsorption process, with ferric chloride and calcium chloride as coprecipitation agents and polymer-based nanocomposite as selective adsorbent, has been validated for arsenic removal from tungsten-smelting wastewater. On the basis of operating optimization, a binary FeCl3 (520 mg/L)-CaCl2 (300 mg/L) coprecipitation agent could remove more than 93% arsenic from the wastewater. The resulting precipitate has proved environmental safety based on leaching toxicity test. Fixed-bed column packed with zirconium or ferric-oxide-loaded nanocomposite was employed for further elimination of arsenic in coprecipitated effluent, resulting in a significant decrease of arsenic (from 0.96 to less than 0.5 mg/L). The working capacity of zirconium-loaded nanocomposite was 220 bed volumes per run, much higher than that of ferric-loaded nanocomposite (40 bed volumes per run). The exhausted zirconium-loaded nanocomposite could be efficiently in situ regenerated with a binary NaOH-NaCl solution for reuse without any significant capacity loss. The results validated the combinational coprecipitation/nano-adsorption process to be a potential alternative for effective arsenic removal from highly laden industrial effluent.

Localized atrophy of the thalamus and slowed cognitive processing speed in MS patients.

PubMed

Bergsland, Niels; Zivadinov, Robert; Dwyer, Michael G; Weinstock-Guttman, Bianca; Benedict, Ralph Hb

2016-09-01

Deep gray matter (DGM) atrophy is common in multiple sclerosis (MS), but no studies have investigated surface-based structure changes over time with respect to healthy controls (HCs). Moreover, the relationship between cognition and the spatio-temporal evolution of DGM atrophy is poorly understood. To explore DGM structural differences between MS and HCs over time in relation to neuropsychological (NP) outcomes. The participants were 44 relapsing-remitting and 20 secondary progressive MS patients and 22 HCs. All were scanned using 3T magnetic resonance imaging (MRI) at baseline and 3-year follow-up. NP examination emphasized consensus standard tests of processing speed and memory. We performed both volumetric and shape analysis of DGM structures and assessed their relationships with cognition. Compared to HCs, MS patients presented with significantly smaller DGM volumes. For the thalamus and caudate, differences in shape were mostly localized along the lateral ventricles. NP outcomes were related to both volume and shape of the DGM structures. Over 3 years, decreased cognitive processing speed was related to localized atrophy on the anterior and superior surface of the left thalamus. These findings highlight the role of atrophy in the anterior nucleus of the thalamus and its relation to cognitive decline in MS. © The Author(s), 2015.

Biorefinery process for protein extraction from oriental mustard (Brassica juncea (L.) Czern.) using ethanol stillage.

PubMed

Ratanapariyanuch, Kornsulee; Tyler, Robert T; Shim, Youn Young; Reaney, Martin Jt

2012-01-12

Large volumes of treated process water are required for protein extraction. Evaporation of this water contributes greatly to the energy consumed in enriching protein products. Thin stillage remaining from ethanol production is available in large volumes and may be suitable for extracting protein rich materials. In this work protein was extracted from ground defatted oriental mustard (Brassica juncea (L.) Czern.) meal using thin stillage. Protein extraction efficiency was studied at pHs between 7.6 and 10.4 and salt concentrations between 3.4 × 10-2 and 1.2 M. The optimum extraction efficiency was pH 10.0 and 1.0 M NaCl. Napin and cruciferin were the most prevalent proteins in the isolate. The isolate exhibited high in vitro digestibility (74.9 ± 0.80%) and lysine content (5.2 ± 0.2 g/100 g of protein). No differences in the efficiency of extraction, SDS-PAGE profile, digestibility, lysine availability, or amino acid composition were observed between protein extracted with thin stillage and that extracted with NaCl solution. The use of thin stillage, in lieu of water, for protein extraction would decrease the energy requirements and waste disposal costs of the protein isolation and biofuel production processes.

Biorefinery process for protein extraction from oriental mustard (Brassica juncea (L.) Czern.) using ethanol stillage

PubMed Central

2012-01-01

Large volumes of treated process water are required for protein extraction. Evaporation of this water contributes greatly to the energy consumed in enriching protein products. Thin stillage remaining from ethanol production is available in large volumes and may be suitable for extracting protein rich materials. In this work protein was extracted from ground defatted oriental mustard (Brassica juncea (L.) Czern.) meal using thin stillage. Protein extraction efficiency was studied at pHs between 7.6 and 10.4 and salt concentrations between 3.4 × 10-2 and 1.2 M. The optimum extraction efficiency was pH 10.0 and 1.0 M NaCl. Napin and cruciferin were the most prevalent proteins in the isolate. The isolate exhibited high in vitro digestibility (74.9 ± 0.80%) and lysine content (5.2 ± 0.2 g/100 g of protein). No differences in the efficiency of extraction, SDS-PAGE profile, digestibility, lysine availability, or amino acid composition were observed between protein extracted with thin stillage and that extracted with NaCl solution. The use of thin stillage, in lieu of water, for protein extraction would decrease the energy requirements and waste disposal costs of the protein isolation and biofuel production processes. PMID:22239856

Pharmacokinetic evidence for improved ophthalmic drug delivery by reduction of instilled volume.

PubMed

Patton, T F

1977-07-01

The bioavailability of topically applied pilocarpine nitrate was studied as a function of instilled volume. As the instilled volume decreased, the fraction of dose absorbed increased. The relationship between fraction absorbed and instilled volume was not direct, but appropriate adjustment of instilled volume and concentration should permit substantial dosage reductions without sacrifice of drug concentration in the eye. The implications of these findings from both a therapeutic and toxicity standpoint are discussed.

Surgically Facilitated Orthodontic Therapy: Optimizing Dentoalveolar Bone and Space Appropriation for Facially Prioritized Interdisciplinary Dentofacial Therapy.

PubMed

Mandelaris, George A; DeGroot, Bradley S; Relle, Robert; Shah, Brian; Huang, Iwei; Vence, Brian S

2018-03-01

Comorbidities that negatively impact orthodontic (malocclusion), periodontal (periodontitis, deficient dentoalveolar bone volume, mucogingival), and prosthetic (structural integrity compromise from caries, attrition, and erosion) conditions can affect the general health of the patient. In addition, emerging data highlights the importance of undiagnosed airway volume deficiencies and sleep-disordered breathing conditions in the adult and pediatric population. Deficiencies in dentoalveolar bone and discrepancies in skeletal relationships can impact the volume of hard- and soft-tissue structures of the periodontium and decrease oral cavity volume. Contemporary interdisciplinary dentofacial therapy (IDT) is a key process for addressing the comprehensive problems of patients based on etiology, homeostasis, and sustainability of physiologically sound outcomes. These provide the patient with sustainable esthetics and function. Surgically facilitated orthodontic therapy (SFOT) uses corticotomies and dentoalveolar bone decortication to stimulate the regional acceleratory phenomenon and upregulate bone remodeling and tooth movement as a part of orthodontic decompensation. It also generally includes guided periodontal tissue regeneration and/or dentoalveolar bone augmentation. SFOT as a part of IDT is demanding and requires extensive attentiveness and communication among all team members. This article focuses on the role of SFOT as an integral component of contemporary IDT to facilitate highly predictable and sustainable outcomes.

The partial volume effect in the quantification of 1H magnetic resonance spectroscopy in Alzheimer's disease and aging.

PubMed

Mato Abad, Virginia; Quirós, Alicia; García-Álvarez, Roberto; Loureiro, Javier Pereira; Alvarez-Linera, Juan; Frank, Ana; Hernández-Tamames, Juan Antonio

2014-01-01

1H-MRS variability increases due to normal aging and also as a result of atrophy in grey and white matter caused by neurodegeneration. In this work, an automatic process was developed to integrate data from spectra and high-resolution anatomical images to quantify metabolites, taking into account tissue partial volumes within the voxel of interest avoiding additional spectra acquisitions required for partial volume correction. To evaluate this method, we use a cohort of 135 subjects (47 male and 88 female, aged between 57 and 99 years) classified into 4 groups: 38 healthy participants, 20 amnesic mild cognitive impairment patients, 22 multi-domain mild cognitive impairment patients, and 55 Alzheimer's disease patients. Our findings suggest that knowing the voxel composition of white and grey matter and cerebrospinal fluid is necessary to avoid partial volume variations in a single-voxel study and to decrease part of the variability found in metabolites quantification, particularly in those studies involving elder patients and neurodegenerative diseases. The proposed method facilitates the use of 1H-MRS techniques in statistical studies in Alzheimer's disease, because it provides more accurate quantitative measurements, reduces the inter-subject variability, and improves statistical results when performing group comparisons.

Significant grey matter changes in a region of the orbitofrontal cortex in healthy participants predicts emotional dysregulation

PubMed Central

Ekman, Carl Johan; Klahr, Johanna; Tigerström, Lars; Rydén, Göran; Johansson, Anette G. M.; Sellgren, Carl; Golkar, Armita; Olsson, Andreas; Öhman, Arne; Ingvar, Martin; Landén, Mikael

2016-01-01

The traditional concept of ‘categorical’ psychiatric disorders has been challenged as many of the symptoms display a continuous distribution in the general population. We suggest that this is the case for emotional dysregulation, a key component in several categorical psychiatric disorder constructs. We used voxel-based magnetic resonance imaging morphometry in healthy human subjects (n = 87) to study how self-reported subclinical symptoms associated with emotional dysregulation relate to brain regions assumed to be critical for emotion regulation. To measure a pure emotional dysregulation, we also corrected for subclinical symptoms of non-emotional attentional dysregulation. We show that such subclinical emotional symptoms correlate negatively with the grey matter volume of lateral orbitofrontal cortex bilaterally—a region assumed to be critical for emotion regulation and dysfunctional in psychiatric disorders involving emotional dysregulation. Importantly, this effect is mediated both by a decrease in volume associated with emotional dysregulation and an increase in volume due to non-emotional attentional dysregulation. Exploratory analysis suggests that other regions involved in emotional processing such as insula and ventral striatum also show a similar reduction in grey matter volume mirroring clinical disorders associated with emotional dysregulation. Our findings support the concept of continuous properties in psychiatric symptomatology. PMID:26078386

Normalized pulse volume (NPV) derived photo-plethysmographically as a more valid measure of the finger vascular tone.

PubMed

Sawada, Y; Tanaka, G; Yamakoshi, K

2001-05-01

Normalized pulse volume (NPV) was advocated as a more valid measure for the assessment of finger vascular tone. Based on the optical model in the finger tip expressed by Lambert--Beer's law, NPV is expressed as Delta I(a)/I. Here, Delta I(a) is the intensity of pulsatile component superimposed on the transmitted light (I). Theoretically, NPV seems to be superior to the conventional pulse volume (PV; corresponding to Delta I(a)). Firstly, NPV is in direct proportion to Delta V(a), which is the pulsatile component of the arterial blood volume, in a more exact manner. Relatedly, NPV can be processed as if it is an absolute value. Secondly, the sensitivity of NPV during stressful stimulations is expected to be higher. These expectations were supported experimentally using 13 male students. Firstly, the correlation between cutaneous vascular resistance in the finger tip (CVR) and NPV was higher than that between CVR and PV among all the subjects, although there was not much difference between these correlations within each subject. Secondly, NPV decreased much more than PV during mental stress. Some limitations of the present study were addressed, including the point that certain factors can violate the direct proportional relationship of NPV and PV to Delta V(a).

Quantitative volumetric analysis of a retinoic acid induced hypoplastic model of chick thymus, using Image-J.

PubMed

Haque, Ayesha; Khan, Muhammad Yunus

2017-09-01

To assess the total volume change in a retinoic acid-induced, hypoplastic model of a chick thymus using Image-J. This experimental study was carried out at the anatomy department of College of Physicians and Surgeons, Islamabad, Pakistan, from February 2009 to February 2010, and comprised fertilised chicken eggs. The eggs were divided into experimental group A and control group C. Group A was injected with 0.3µg of retinoic acid via yolk sac to induce a defective model of a thymus with hypoplasia. The chicks were sacrificed on embryonic day 15 and at hatching. The thymus of each animal was processed, serially sectioned and stained. The total area of each section of thymus was calculated using Image-J. This total area was summed and multiplied with the thickness of each section to obtain volume. Of the 120 eggs, there were 60(50%) in each group. Image analysis revealed a highly significant decrease in the volume of the chick thymus in the experimental group A than its matched control at the time of hatching (p=0.001). Moreover, volumetric depletion progressed with time, being substantially pronounced at hatching compared to the embryonic stage. The volume changes were significant and were effectively quantified using Image-J.

Formation mechanism of a silicon carbide coating for a reinforced carbon-carbon composite

NASA Technical Reports Server (NTRS)

Rogers, D. C.; Shuford, D. M.; Mueller, J. I.

1975-01-01

Results are presented for a study to determine the mechanisms involved in a high-temperature pack cementation process which provides a silicon carbide coating on a carbon-carbon composite. The process and materials used are physically and chemically analyzed. Possible reactions are evaluated using the results of these analytical data. The coating is believed to develop in two stages. The first is a liquid controlled phase process in which silicon carbide is formed due to reactions between molten silicon metal and the carbon. The second stage is a vapor transport controlled reaction in which silicon vapors react with the carbon. There is very little volume change associated with the coating process. The original thickness changes by less than 0.7%. This indicates that the coating process is one of reactive penetration. The coating thickness can be increased or decreased by varying the furnace cycle process time and/or temperature to provide a wide range of coating thicknesses.

Water quality management library. 2. edition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eckenfelder, W.W.; Malina, J.F.; Patterson, J.W.

1998-12-31

A series of ten books offered in conjunction with Water Quality International, the Biennial Conference and Exposition of the International Association on Water Pollution Research and Control (IAWPRC). Volume 1, Activated Sludge Process, Design and Control, 2nd edition, 1998: Volume 2, Upgrading Wastewater Treatment Plants, 2nd edition, 1998: Volume 3, Toxicity Reduction, 2nd edition, 1998: Volume 4, Municipal Sewage Sludge Management, 2nd edition, 1998: Volume 5, Design and Retrofit of Wastewater Treatment Plants for Biological Nutrient Removal, 1st edition, 1992: Volume 6, Dynamics and Control of the Activated Sludge Process, 2nd edition, 1998: Volume 7: Design of Anaerobic Processes formore » the Treatment of Industrial and Municipal Wastes, 1st edition, 1992: Volume 8, Groundwater Remediation, 1st edition, 1992: Volume 9, Nonpoint Pollution and Urban Stormwater Management, 1st edition, 1995: Volume 10, Wastewater Reclamation and Reuse, 1st edition, 1998.« less

The Effect of Lung Stretch during Sleep on Airway Mechanics in Overweight and Obese Asthma

PubMed Central

Campana, L.M.; Malhotra, A.; Suki, B.; Hess, L.; Israel, E.; Smales, E.; DeYoung, P.; Owens, R.L.

2012-01-01

Both obesity and sleep reduce lung volume and limit deep breaths, possibly contributing to asthma. We hypothesize that increasing lung volume dynamically during sleep would reduce airway resistance in asthma. Asthma (n=10) and control (n=10) subjects were studied during sleep at baseline and with increased lung volume via bi-level positive airway pressure (BPAP). Using forced oscillations, respiratory system resistance (Rrs) and reactance (Xrs) were measured during sleep and Rrs was partitioned to upper and lower airway resistance (Rup, Rlow) using an epiglottic pressure catheter. Rrs and Rup increased with sleep (p<0.01) and Xrs was decreased in REM (p=0.02) as compared to wake. Rrs, Rup, and Rlow, were larger (p<0.01) and Xrs was decreased (p<0.02) in asthma. On BPAP, Rrs and Rup were decreased (p<0.001) and Xrs increased (p<0.01), but Rlow was unchanged. High Rup was observed in asthma, which reduced with BPAP. We conclude that the upper airway is a major component of Rrs and larger lung volume changes may be required to alter Rlow. PMID:23041446

Static lung compliance and body pressures in Tupinambis merianae with and without post-hepatic septum.

PubMed

Klein, Wilfried; Abe, Augusto S; Perry, Steven F

2003-04-15

The surgical removal of the post-hepatic septum (PHS) in the tegu lizard, Tupinambis merianae, significantly reduces resting lung volume (V(Lr)) and maximal lung volume (V(Lm)) when compared with tegus with intact PHS. Standardised for body mass (M(B)), static lung compliance was significantly less in tegus without PHS. Pleural and abdominal pressures followed, like ventilation, a biphasic pattern. In general, pressures increased during expiration and decreased during inspiration. However, during expiration pressure changes showed a marked intra- and interindividual variation. The removal of the PHS resulted in a lower cranio-caudal intracoelomic pressure differential, but had no effect on the general pattern of pressure changes accompanying ventilation. These results show that a perforated PHS that lacks striated muscle has significant influence on static breathing mechanics in Tupinambis and by analogy provides valuable insight into similar processes that led to the evolution of the mammalian diaphragm.

Physiological volume regulation by spermatozoa.

PubMed

Yeung, C H; Barfield, J P; Cooper, T G

2006-05-16

Maturing spermatozoa passing through the epididymis experience increasing osmolality in the luminal environment and mature cells are stored in fluids hyper-osmotic to serum. When ejaculated into the female tract, they encounter a hypo-osmotic challenge which initiates the process of regulatory volume decrease (RVD). Defects in RVD result in hindrance of mucus penetration in man and failure of utero-tubal passage in mice. Epididymal sperm from the mouse and cynomolgus monkey and ejaculated sperm from man and monkey have been isolated and dispersed in media with osmolalities mimicking those of uterine fluid or cervical mucus. The effects of specific and broad-spectrum ion channel blockers indicate the involvement of separate K+ and Cl- channels as well as organic osmolytes in physiological sperm RVD, with mechanisms developed during epididymal maturation. Western blotting and immuno-cytochemistry identify and localise some of these channels which play a crucial role in fertilisation in vivo and could be targets for post-testicular contraception.

Numerical modeling of heat transfer and pasteurizing value during thermal processing of intact egg.

PubMed

Abbasnezhad, Behzad; Hamdami, Nasser; Monteau, Jean-Yves; Vatankhah, Hamed

2016-01-01

Thermal Pasteurization of Eggs, as a widely used nutritive food, has been simulated. A three-dimensional numerical model, computational fluid dynamics codes of heat transfer equations using heat natural convection, and conduction mechanisms, based on finite element method, was developed to study the effect of air cell size and eggshell thickness. The model, confirmed by comparing experimental and numerical results, was able to predict the temperature profiles, the slowest heating zone, and the required heating time during pasteurization of intact eggs. The results showed that the air cell acted as a heat insulator. Increasing the air cell volume resulted in decreasing of the heat transfer rate, and the increasing the required time of pasteurization (up to 14%). The findings show that the effect on thermal pasteurization of the eggshell thickness was not considerable in comparison to the air cell volume.

Measurement and Analysis of Porosity in Al-10Si-1Mg Components Additively Manufactured by Selective Laser Melting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rao, Suraj; Cunningham, Ross; Ozturk, Tugce

Aluminum alloys are candidate materials for weight critical applications because of their excellent strength and stiffness to weight ratio. However, defects such as voids decrease the strength and fatigue life of these alloys, which can limit the application of Selective Laser Melting. In this study, the average volume fraction, average size, and size distribution of pores in Al10-Si-1Mg samples built using Selective Laser Melting have been characterized. Synchrotron high energy X-rays were used to perform computed tomography on volumes of order one cubic millimeter with a resolution of approximately 1.5 μm. Substantial variations in the pore size distributions were foundmore » as a function of process conditions. Even under conditions that ensured that all locations were melted at least once, a significant number density was found of pores above 5 μm in diameter.« less

Influence of liquid-volume and airflow rates on spray application quality and homogeneity in super-intensive olive tree canopies.

PubMed

Miranda-Fuentes, Antonio; Rodríguez-Lizana, Antonio; Gil, Emilio; Agüera-Vega, J; Gil-Ribes, Jesús A

2015-12-15

Olive is a key crop in Europe, especially in countries around the Mediterranean Basin. Optimising the parameters of a spray is essential for sustainable pesticide use, especially in high-input systems, such as the super-intensive hedgerow system. Parameters may be optimised by adjusting the applied volume and airflow rate of sprays, in addition to the liquid to air proportion and the relationship between air velocity and airflow rate. Two spray experiments using a commercial airblast sprayer were conducted in a super-intensive orchard to study how varying the liquid volume rate (testing volumes of 182, 619, and 1603 l ha(-1)) and volumetric airflow rate (with flow rates of 11.93, 8.90, and 6.15 m(3) s(-1)) influences the coverage parameters and the amount and distribution of deposits in different zones of the canopy.. Our results showed that an increase in the application volume raised the mean deposit and percentage coverage, but decreased the application efficiency, spray penetration, and deposit homogeneity. Furthermore, we found that the volumetric airflow rate had a lower influence on the studied parameters than the liquid volume; however, an increase in the airflow rate improved the application efficiency and homogeneity to a certain threshold, after which the spray quality decreased. This decrease was observed in the high-flow treatment. Our results demonstrate that intermediate liquid volume rates and volumetric airflow rates are required for the optimal spraying of pesticides on super-intensive olive crops, and would reduce current pollution levels. Copyright © 2015 Elsevier B.V. All rights reserved.

Fluoride Induces a Volume Reduction in CA1 Hippocampal Slices Via MAP Kinase Pathway Through Volume Regulated Anion Channels

PubMed Central

Lee, Jaekwang; Han, Young-Eun; Favorov, Oleg; Tommerdahl, Mark; Whitsel, Barry

2016-01-01

Regulation of cell volume is an important aspect of cellular homeostasis during neural activity. This volume regulation is thought to be mediated by activation of specific transporters, aquaporin, and volume regulated anion channels (VRAC). In cultured astrocytes, it was reported that swelling-induced mitogen-activated protein (MAP) kinase activation is required to open VRAC, which are thought to be important in regulatory volume decrease and in the response of CNS to trauma and excitotoxicity. It has been also described that sodium fluoride (NaF), a recognized G-protein activator and protein phosphatase inhibitor, leads to a significant MAP kinase activation in endothelial cells. However, NaF's effect in volume regulation in the brain is not known yet. Here, we investigated the mechanism of NaF-induced volume change in rat and mouse hippocampal slices using intrinsic optical signal (IOS) recording, in which we measured relative changes in intracellular and extracellular volume as changes in light transmittance through brain slices. We found that NaF (1~5 mM) application induced a reduction in light transmittance (decreased volume) in CA1 hippocampus, which was completely reversed by MAP kinase inhibitor U0126 (10 µM). We also observed that NaF-induced volume reduction was blocked by anion channel blockers, suggesting that NaF-induced volume reduction could be mediated by VRAC. Overall, our results propose a novel molecular mechanism of NaF-induced volume reduction via MAP kinase signaling pathway by activation of VRAC. PMID:27122993

Attribution of regional flood changes based on scaling fingerprints

NASA Astrophysics Data System (ADS)

Viglione, A.; Merz, B.; Dung, N.; Parajka, J.; Nester, T.; Bloeschl, G.

2017-12-01

Changes in the river flood regime may be due to atmospheric processes (e.g., increasing precipitation), catchment processes (e.g., soil compaction associated with land use change), and river system processes (e.g., loss of retention volume in the floodplains). We propose a framework for attributing flood changes to these drivers based on a regional analysis. We exploit the scaling characteristics (i.e., fingerprints) with catchment area of the effects of the drivers on flood changes. The estimation of their relative contributions is framed in Bayesian terms. Analysis of a synthetic, controlled case suggests that the accuracy of the regional attribution increases with increasing number of sites and record lengths, decreases with increasing regional heterogeneity, increases with increasing difference of the scaling fingerprints, and decreases with an increase of their prior uncertainty. The applicability of the framework is illustrated for a case study set in Austria, where positive flood trends have been observed at many sites in the past decades. The individual scaling fingerprints related to the atmospheric, catchment, and river system processes are estimated from rainfall data and simple hydrological modeling. Although the distributions of the contributions are rather wide, the attribution identifies precipitation change as the main driver of flood change in the study region.

Modeling solubility of CO2/hydrocarbon gas in ionic liquid ([emim][FAP]) using Aspen Plus simulations.

PubMed

Bagchi, Bishwadeep; Sati, Sushmita; Shilapuram, Vidyasagar

2017-08-01

The Peng-Robinson equation of state with quadratic van der Waals (vdW) mixing rule model was chosen to perform the thermodynamic calculations in Flash3 column of Aspen Plus to predict the solubility of CO 2 or any one of the hydrocarbons (HCs) among methane, ethane, propane, and butane in an ionic liquid 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate ([emim][FAP]). Bubble point pressure, solubility, bubble point temperature, fugacity, and partial molar volume at infinite dilution were obtained from the simulations, and enthalpy of absorption, Gibbs free energy of solvation, and entropy change of absorption were estimated by thermodynamic relations. Results show that carbon chain length has a significant effect on the bubble point pressure. Methane has the highest bubble point pressure among all the considered HCs and CO 2 . The bubble point pressure and fugacity variation with temperature is different for CO 2 as compared to HCs for mole fractions above 0.2. Two different profiles are noticed for enthalpy of absorption when plotted as a function of mole fraction of gas soluble in IL. Partial molar volume of CO 2 decreases with increase in temperature in [emim][FAP], while it is increased for HCs. Bubble point temperature decreases with increase in the mole fraction of the solute. Entropy of solvation increases with temperature till a particular value followed by a decrease with further increase in temperature. Gibbs free energy change of solvation showed that the process of solubility was spontaneous.

Framework Programmable Platform for the Advanced Software Development Workstation (FPP/ASDW). Demonstration framework document. Volume 2: Framework process description

NASA Technical Reports Server (NTRS)

Mayer, Richard J.; Blinn, Thomas M.; Dewitte, Paula S.; Crump, John W.; Ackley, Keith A.

1992-01-01

In the second volume of the Demonstration Framework Document, the graphical representation of the demonstration framework is given. This second document was created to facilitate the reading and comprehension of the demonstration framework. It is designed to be viewed in parallel with Section 4.2 of the first volume to help give a picture of the relationships between the UOB's (Unit of Behavior) of the model. The model is quite large and the design team felt that this form of presentation would make it easier for the reader to get a feel for the processes described in this document. The IDEF3 (Process Description Capture Method) diagrams of the processes of an Information System Development are presented. Volume 1 describes the processes and the agents involved with each process, while this volume graphically shows the precedence relationships among the processes.

Depressive Symptoms in Adolescents: Associations with White Matter Volume and Marijuana Use

ERIC Educational Resources Information Center

Medina, Krista Lisdahl; Nagel, Bonnie J.; Park, Ann; McQueeny, Tim; Tapert, Susan F.

2007-01-01

Background: Depressed mood has been associated with decreased white matter and reduced hippocampal volumes. However, the relationship between brain structure and mood may be unique among adolescents who use marijuana heavily. The goal of this study was to examine the relationship between white matter and hippocampal volumes and depressive symptoms…

30 CFR 250.1623 - Well-control fluids, equipment, and operations.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., (2) A well-control fluid-volume measuring device for determining fluid volumes when filling the hole on trips, and (3) A recording mud-pit-level indicator to determine mud-pit-volume gains and losses... the change in fluid level decreases the hydrostatic pressure 75 psi or every five stands of drill pipe...

A volume change index for forest growth and sustainability

Treesearch

Paul Van Deusen; Francis Roesch

2009-01-01

A volume change index is suggested that is derived from growth components that can be estimated from remeasured plots. The new index incorporates more information than the traditional growth over removals, ratio. The new index directly indicates whether the standing volume will be increasing or decreasing if current conditions persist, whereas the ratio of...

Drivers of U.S. toxicological footprints trajectory 1998-2013

NASA Astrophysics Data System (ADS)

Koh, S. C. L.; Ibn-Mohammed, T.; Acquaye, A.; Feng, K.; Reaney, I. M.; Hubacek, K.; Fujii, H.; Khatab, K.

2016-12-01

By exploiting data from the Toxic Release Inventory of the United States, we have established that the toxicological footprint (TF) increased by 3.3% (88.4 Mt) between 1998 and 1999 and decreased by 39% (1088.5 Mt) between 1999 and 2013. From 1999 to 2006, the decreasing TF was driven by improvements in emissions intensity (i.e. gains in production efficiency) through toxic chemical management options: cleaner production; end of pipe treatment; transfer for further waste management; and production scale. In particular, the mining sector reduced its TF through outsourcing processes. Between 2006 and 2009, decreasing TF was due to decrease in consumption volume triggered by economic recession. Since 2009, the economic recovery increased TF, overwhelming the influence of improved emissions intensity through population growth, consumption and production structures. Accordingly, attaining a less-toxic economy and environment will be influenced by a combination of gains in production efficiency through improvement in emissions mitigation technologies and changes in consumption patterns. Overall, the current analysis highlights the structural dynamics of toxic chemical release and would inform future formulation of effective mitigation standards and management protocols towards the detoxification of the environment.

Lung volumes during sustained microgravity on Spacelab SLS-1

NASA Technical Reports Server (NTRS)

Elliott, Ann R.; Prisk, Gordon Kim; Guy, Harold J. B.; West, John B.

1994-01-01

Gravity is known to influence the topographical gradients of pulmonary ventilation, perfusion, and pleural pressures. The effect of sustained microgravity on lung volumes has not previously been investigated. Pulmonary function tests were performed by four subjects before, during, and after 9 days of microgravity exposure. Ground measurements were made in standing and supine postures. Tests were performed using a bag-in-box and flowmeter system and a respiratory mass spectrometer. Measurements of tidal volume (V(sub T)), expiratory reserve volume (ERV), inspiratory and expiratory vital capacities (IVC, EVC), functional residual capacity (FRC), and residual volume (RV) were made. During microgravity, V(sub T) decreased by 15%. IVC and EVC were slightly reduced during the first 24 hrs of microgravity and returned to 1 g standing values within 72 hrs after the onset of microgravity. FRC was reduced by 15% and ERV decreased by 10-20%. RV was significantly reduced by 18%. The reductions in FRC, ERV, and V(sub T) during microgravity are probably due to the cranial shift of the diaphragm and an increase in intrathoracic blood volume.

Accuracy of implementing principles of fusion imaging in the follow up and surveillance of complex aneurysm repair.

PubMed

Martin-Gonzalez, Teresa; Penney, Graeme; Chong, Debra; Davis, Meryl; Mastracci, Tara M

2018-05-01

Fusion imaging is standard for the endovascular treatment of complex aortic aneurysms, but its role in follow up has not been explored. A critical issue is renal function deterioration over time. Renal volume has been used as a marker of renal impairment; however, it is not reproducible and remains a complex and resource-intensive procedure. The aim of this study is to determine the accuracy of a fusion-based software to automatically calculate the renal volume changes during follow up. In this study, computerized tomography (CT) scans of 16 patients who underwent complex aortic endovascular repair were analysed. Preoperative, 1-month and 1-year follow-up CT scans have been analysed using a conventional approach of semi-automatic segmentation, and a second approach with automatic segmentation. For each kidney and at each time point the percentage of change in renal volume was calculated using both techniques. After review, volume assessment was feasible for all CT scans. For the left kidney, the intraclass correlation coefficient (ICC) was 0.794 and 0.877 at 1 month and 1 year, respectively. For the right side, the ICC was 0.817 at 1 month and 0.966 at 1 year. The automated technique reliably detected a decrease in renal volume for the eight patients with occluded renal arteries during follow up. This is the first report of a fusion-based algorithm to detect changes in renal volume during postoperative surveillance using an automated process. Using this technique, the standardized assessment of renal volume could be implemented with greater ease and reproducibility and serve as a warning of potential renal impairment.

The impact of PET/CT scanning on the size of target volumes, radiation exposure of organs at risk, TCP and NTCP, in the radiotherapy planning of non-small cell lung cancer.

PubMed

Vojtíšek, Radovan; Mužík, Jan; Slampa, Pavel; Budíková, Marie; Hejsek, Jaroslav; Smolák, Petr; Ferda, Jiří; Fínek, Jindřich

2014-05-01

To compare radiotherapy plans made according to CT and PET/CT and to investigate the impact of changes in target volumes on tumour control probability (TCP), normal tissue complication probability (NTCP) and the impact of PET/CT on the staging and treatment strategy. Contemporary studies have proven that PET/CT attains higher sensitivity and specificity in the diagnosis of lung cancer and also leads to higher accuracy than CT alone in the process of target volume delineation in NSCLC. Between October 2009 and March 2012, 31 patients with locally advanced NSCLC, who had been referred to radical radiotherapy were involved in our study. They all underwent planning PET/CT examination. Then we carried out two separate delineations of target volumes and two radiotherapy plans and we compared the following parameters of those plans: staging, treatment purpose, the size of GTV and PTV and the exposure of organs at risk (OAR). TCP and NTCP were also compared. PET/CT information led to a significant decrease in the sizes of target volumes, which had the impact on the radiation exposure of OARs. The reduction of target volume sizes was not reflected in the significant increase of the TCP value. We found that there is a very strong direct linear relationship between all evaluated dosimetric parameters and NTCP values of all evaluated OARs. Our study found that the use of planning PET/CT in the radiotherapy planning of NSCLC has a crucial impact on the precise determination of target volumes, more precise staging of the disease and thus also on possible changes of treatment strategy.

A Retrospective Belgian Multi-Center MRI Biomarker Study in Alzheimer's Disease (REMEMBER).

PubMed

Niemantsverdriet, Ellis; Ribbens, Annemie; Bastin, Christine; Benoit, Florence; Bergmans, Bruno; Bier, Jean-Christophe; Bladt, Roxanne; Claes, Lene; De Deyn, Peter Paul; Deryck, Olivier; Hanseeuw, Bernard; Ivanoiu, Adrian; Lemper, Jean-Claude; Mormont, Eric; Picard, Gaëtane; Salmon, Eric; Segers, Kurt; Sieben, Anne; Smeets, Dirk; Struyfs, Hanne; Thiery, Evert; Tournoy, Jos; Triau, Eric; Vanbinst, Anne-Marie; Versijpt, Jan; Bjerke, Maria; Engelborghs, Sebastiaan

2018-01-01

Magnetic resonance imaging (MRI) acquisition/processing techniques assess brain volumes to explore neurodegeneration in Alzheimer's disease (AD). We examined the clinical utility of MSmetrix and investigated if automated MRI volumes could discriminate between groups covering the AD continuum and could be used as a predictor for clinical progression. The Belgian Dementia Council initiated a retrospective, multi-center study and analyzed whole brain (WB), grey matter (GM), white matter (WM), cerebrospinal fluid (CSF), cortical GM (CGM) volumes, and WM hyperintensities (WMH) using MSmetrix in the AD continuum. Baseline (n = 887) and follow-up (FU, n = 95) T1-weighted brain MRIs and time-linked neuropsychological data were available. The cohort consisted of cognitively healthy controls (HC, n = 93), subjective cognitive decline (n = 102), mild cognitive impairment (MCI, n = 379), and AD dementia (n = 313). Baseline WB and GM volumes could accurately discriminate between clinical diagnostic groups and were significantly decreased with increasing cognitive impairment. MCI patients had a significantly larger change in WB, GM, and CGM volumes based on two MRIs (n = 95) compared to HC (FU>24months, p = 0.020). Linear regression models showed that baseline atrophy of WB, GM, CGM, and increased CSF volumes predicted cognitive impairment. WB and GM volumes extracted by MSmetrix could be used to define the clinical spectrum of AD accurately and along with CGM, they are able to predict cognitive impairment based on (decline in) MMSE scores. Therefore, MSmetrix can support clinicians in their diagnostic decisions, is able to detect clinical disease progression, and is of help to stratify populations for clinical trials.

Melting properties of Pt and its transport coefficients in liquid states under high pressures

NASA Astrophysics Data System (ADS)

Wang, Pan-Pan; Shao, Ju-Xiang; Cao, Qi-Long

2016-11-01

Molecular dynamics (MD) simulations of the melting and transport properties in liquid states of platinum for the pressure range (50-200 GPa) are reported. The melting curve of platinum is consistent with previous ab initio MD simulation results and the first-principles melting curve. Calculated results for the pressure dependence of fusion entropy and fusion volume show that the fusion entropy and the fusion volume decrease with increasing pressure, and the ratio of the fusion volume to fusion entropy roughly reproduces the melting slope, which has a moderate decrease along the melting line. The Arrhenius law well describes the temperature dependence of self-diffusion coefficients and viscosity under high pressure, and the diffusion activation energy decreases with increasing pressure, while the viscosity activation energy increases with increasing pressure. In addition, the entropy-scaling law, proposed by Rosenfeld under ambient pressure, still holds well for liquid Pt under high pressure conditions.

Communication: Influence of nanophase segregation on ion transport in room temperature ionic liquids

DOE PAGES

Griffin, Philip J.; Wang, Yangyang; Holt, Adam P.; ...

2016-04-21

In this paper, we report measurements of the ionic conductivity, shear viscosity, and structural dynamics in a homologous series of quaternary ammonium ionic liquids (ILs) and a prototypical imidazolium-based IL over a wide range of temperatures down to the glass transition. We find that the ionic conductivity of these materials generally decreases, while the shear viscosity correspondingly increases, with increasing volume fraction of aliphatic side groups. Upon crossing an aliphatic volume fraction of ~0.40, we observe a sharp, order-of-magnitude decrease in ionic conductivity and enhancement of viscosity, which coincides with the presence of long-lived, nanometer-sized alkyl aggregates. These strong changesmore » in dynamics are not mirrored in the ionicity of these ILs, which decreases nearly linearly with aliphatic volume fraction. Finally, our results demonstrate that nanophase segregation in neat ILs strongly reduces ionic conductivity primarily due to an aggregation-induced suppression of dynamics.« less

[Lung dysfunction in patients with severe chronic obstructive bronchitis].

PubMed

Nefedov, V B; Popova, L A; Shergina, E A

2005-01-01

VC, FVC, FEV1, FEV1/VC%, PEF, MEF25, MEF50, MEF75, TCL, TGV, RV, Raw, Rin, Rex, DLCO-SS, PaO2, and PaCO2 were determined in 36 patients with severe chronic obstructive lung disease (FEV1 < 50% of the normal value). All the patients were found to have impaired bronchial patency and changes in lung volumes and capacities; 83.3% of the patients had pulmonary gas exchange dysfunction. Impaired bronchial patency mainly appeared as decreased FEV1, FEV1/VC%, PEF, MEF25, MEF50, MEF75, Raw, Rin, Rex; altered lung volumes and capacities manifested by increased RV, TGV, and TLC, and by decreased VC and FVC; pulmonary gas exchange dysfunction showed up as lowered PaO2 and DLCO-SS, as decreased or increased PaCO2. The observed bronchial patency disorders varied from significant to severe; functional changes in lung volumes and capacities were mild to severe.

Impact of obstructive sleep apnea on lung volumes and mechanical properties of the respiratory system in overweight and obese individuals.

PubMed

Abdeyrim, Arikin; Zhang, Yongping; Li, Nanfang; Zhao, Minghua; Wang, Yinchun; Yao, Xiaoguang; Keyoumu, Youledusi; Yin, Ting

2015-07-25

Even through narrowing of the upper-airway plays an important role in the generation of obstructive sleep apnea (OSA), the peripheral airways is implicated in pre-obese and obese OSA patients, as a result of decreased lung volume and increased lung elastic recoil pressure, which, in turn, may aggravate upper-airway collapsibility. A total of 263 male (n = 193) and female (n = 70) subjects who were obese to various degrees without a history of lung diseases and an expiratory flow limitation, but troubled with snoring or suspicion of OSA were included in this cross-sectional study. According to nocturnal-polysomnography the subjects were distributed into OSA and non-OSA groups, and were further sub-grouped by gender because of differences between males and females, in term of, lung volume size, airway resistance, and the prevalence of OSA among genders. Lung volume and respiratory mechanical properties at different-frequencies were evaluated by plethysmograph and an impulse oscillation system, respectively. Functional residual capacity (FRC) and expiratory reserve volume were significantly decreased in the OSA group compared to the non-OSA group among males and females. As weight and BMI in males in the OSA group were greater than in the non-OSA group (90 ± 14.8 kg vs. 82 ± 10.4 kg, p < 0.001; 30.5 ± 4.2 kg/m(2) vs. 28.0 ± 3.0 kg/m(2), p < 0.001), multiple regression analysis was required to adjust for BMI or weight and demonstrated that these lung volumes decreases were independent from BMI and associated with the severity of OSA. This result was further confirmed by the female cohort. Significant increases in total respiratory resistance and decreases in respiratory conductance (Grs) were observed with increasing severity of OSA, as defined by the apnea-hypopnea index (AHI) in both genders. The specific Grs (sGrs) stayed relatively constant between the two groups in woman, and there was only a weak association between AHI and sGrs among man. Multiple-stepwise-regression showed that reactance at 5 Hz was highly correlated with AHI in males and females or hypopnea index in females, independently-highly correlated with peripheral-airway resistance and significantly associated with decreasing FRC. Total respiratory resistance and peripheral airway resistance significantly increase, and its inverse Grs decrease, in obese patients with OSA in comparison with those without OSA, and are independently associated with OSA severity. These results might be attributed to the abnormally increased lung elasticity recoil pressure on exhalation, due to increase in lung elasticity and decreased lung volume in obese OSA.

Monitoring cell morphology during necrosis and apoptosis by quantitative phase imaging

NASA Astrophysics Data System (ADS)

Mugnano, Martina; Calabuig, Alejandro; Grilli, Simonetta; Miccio, Lisa; Ferraro, Pietro

2015-05-01

Cellular morphology changes and volume alterations play significant roles in many biological processes and they are mirrors of cell functions. In this paper, we propose the Digital Holographic microscope (DH) as a non-invasive imaging technique for a rapid and accurate extraction of morphological information related to cell death. In particular, we investigate the morphological variations that occur during necrosis and apoptosis. The study of necrosis is extremely important because it is often associated with unwarranted loss of cells in human pathologies such as ischemia, trauma, and some forms of neurodegeneration; therefore, a better elucidation in terms of cell morphological changes could pave the way for new treatments. Also, apoptosis is extremely important because it's involved in cancer, both in its formation and in medical treatments. Because the inability to initiate apoptosis enhances tumour formation, current cancer treatments target this pathway. Within this framework, we have developed a transmission off-axis DH apparatus integrated with a micro incubator for investigation of living cells in a temperature and CO2 controlled environment. We employ DH to analyse the necrosis cell death induced by laser light (wavelength 473 nm, light power 4 mW). We have chosen as cellular model NIH 3T3 mouse embryonic fibroblasts because their adhesive features such as morphological changes, and the time needed to adhere and spread have been well characterized in the literature. We have monitored cell volume changes and morphological alterations in real time in order to study the necrosis process accurately and quantitatively. Cell volume changes were evaluated from the measured phase changes of light transmitted through cells. Our digital holographic experiments showed that after exposure of cells to laser light for 90-120 min., they swell and then take on a balloon-like shape until the plasma membrane ruptures and finally the cell volume decreases. Furthermore, we present a preliminary study on the variation of morphological parameters in case of cell apoptosis induced by exposure to 10 μM cadmium chloride. We employ the same cell line, monitoring the process for 18 hours. In the vast group of environmental pollutants, the toxic heavy metal cadmium is considered a likely candidate as a causative agent of several types of cancers. Widely distributed and used in industry, and with a broad range of target organs and a long half-life (10-30 years) in the human body, this element has been long known for its multiple adverse effects on human health, through occupational or environmental exposure. In apoptosis, we measure cell volume decrease and cell shrinking. Both data of apoptosis and necrosis were analysed by means of a Sigmoidal Statistical Distribution function, which allows several quantitative data to be established, such as swelling and cell death time, flux of intracellular material from inside to outside the cell, initial and final volume versus time. In addition, we can quantitatively study the cytoplasmatic granularity that occurs during necrosis. As a future application, DH could be employed as a non-invasive and label-free method to distinguish between apoptosis and necrosis in terms of morphological parameters.

TRPV4 and AQP4 Channels Synergistically Regulate Cell Volume and Calcium Homeostasis in Retinal Müller Glia

PubMed Central

Jo, Andrew O.; Phuong, Tam T.T.; Verkman, Alan S.; Yarishkin, Oleg; MacAulay, Nanna

2015-01-01

Brain edema formation occurs after dysfunctional control of extracellular volume partly through impaired astrocytic ion and water transport. Here, we show that such processes might involve synergistic cooperation between the glial water channel aquaporin 4 (AQP4) and the transient receptor potential isoform 4 (TRPV4), a polymodal swelling-sensitive cation channel. In mouse retinas, TRPV4 colocalized with AQP4 in the end feet and radial processes of Müller astroglia. Genetic ablation of TRPV4 did not affect the distribution of AQP4 and vice versa. However, retinas from Trpv4−/− and Aqp4−/− mice exhibited suppressed transcription of genes encoding Trpv4, Aqp4, and the Kir4.1 subunit of inwardly rectifying potassium channels. Swelling and [Ca2+]i elevations evoked in Müller cells by hypotonic stimulation were antagonized by the selective TRPV4 antagonist HC-067047 (2-methyl-1-[3-(4-morpholinyl)propyl]-5-phenyl-N-[3-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide) or Trpv4 ablation. Elimination of Aqp4 suppressed swelling-induced [Ca2+]i elevations but only modestly attenuated the amplitude of Ca2+ signals evoked by the TRPV4 agonist GSK1016790A [(N-((1S)-1-{[4-((2S)-2-{[(2,4-dichlorophenyl)sulfonyl]amino}-3-hydroxypropanoyl)-1-piperazinyl]carbonyl}-3-methylbutyl)-1-benzothiophene-2-carboxamide]. Glial cells lacking TRPV4 but not AQP4 showed deficits in hypotonic swelling and regulatory volume decrease. Functional synergy between TRPV4 and AQP4 during cell swelling was confirmed in the heterologously expressing Xenopus oocyte model. Importantly, when the swelling rate was osmotically matched for AQP4-positive and AQP4-negative oocytes, TRPV4 activation became independent of AQP4. We conclude that AQP4-mediated water fluxes promote the activation of the swelling sensor, whereas Ca2+ entry through TRPV4 channels reciprocally modulates volume regulation, swelling, and Aqp4 gene expression. Therefore, TRPV4–AQP4 interactions constitute a molecular system that fine-tunes astroglial volume regulation by integrating osmosensing, calcium signaling, and water transport and, when overactivated, triggers pathological swelling. SIGNIFICANCE STATEMENT We characterize the physiological features of interactions between the astroglial swelling sensor transient receptor potential isoform 4 (TRPV4) and the aquaporin 4 (AQP4) water channel in retinal Müller cells. Our data reveal an elegant and complex set of mechanisms involving reciprocal interactions at the level of glial gene expression, calcium homeostasis, swelling, and volume regulation. Specifically, water influx through AQP4 drives calcium influx via TRPV4 in the glial end foot, which regulates expression of Aqp4 and Kir4.1 genes and facilitates the time course and amplitude of hypotonicity-induced swelling and regulatory volume decrease. We confirm the crucial facets of the signaling mechanism in heterologously expressing oocytes. These results identify the molecular mechanism that contributes to dynamic regulation of glial volume but also provide new insights into the pathophysiology of glial reactivity and edema formation. PMID:26424896

Effects of heart rate on experimentally produced mitral regurgitation in dogs.

PubMed

Yoran, C; Yellin, E L; Hori, M; Tsujioka, K; Laniado, S; Sonnenblick, E H; Frater, R W

1983-12-01

The effects of increasing heart rate (HR) on the hemodynamics of acute mitral regurgitation (MR) were studied in 8 open-chest dogs. Filling volume, regurgitant volume and stroke volume were calculated from electromagnetic probe measurements of mitral and aortic flows. The left atrial-left ventricular systolic pressure gradient was measured with micromanometers. The calculated effective mitral regurgitant orifice area varied from 10 to 128 mm2, with a consequent regurgitant fraction (regurgitant volume/filling volume) of 24 to 62%. After crushing the sinus node, HR was increased stepwise from 90 to 180 beats/min by atrial pacing while maintaining aortic pressure constant. With increasing HR, filling volume, stroke volume, regurgitant volume and regurgitant time decreased; total cardiac output, forward cardiac output, regurgitant output, systolic pressure gradient, regurgitant fraction and the regurgitant orifice did not change; left ventricular end-diastolic pressure decreased; and left atrial v-wave amplitude increased. These results indicate that in acute experimental MR with a wide spectrum of incompetence, the relative distribution of forward and regurgitant flows did not change with large increases in HR. At rates greater than 150 beats/min the atrial contraction occurs early and increases the amplitude of the left atrial v wave. This may contribute to the severity of pulmonary congestion in patients with MR.

A Novel Approach for Using Dielectric Spectroscopy to Predict Viable Cell Volume (VCV) in Early Process Development

PubMed Central

Downey, Brandon J; Graham, Lisa J; Breit, Jeffrey F; Glutting, Nathaniel K

2014-01-01

Online monitoring of viable cell volume (VCV) is essential to the development, monitoring, and control of bioprocesses. The commercial availability of steam-sterilizable dielectric-spectroscopy probes has enabled successful adoption of this technology as a key noninvasive method to measure VCV for cell-culture processes. Technological challenges still exist, however. For some cell lines, the technique's accuracy in predicting the VCV from probe-permittivity measurements declines as the viability of the cell culture decreases. To investigate the cause of this decrease in accuracy, divergences in predicted vs. actual VCV measurements were directly related to the shape of dielectric frequency scans collected during a cell culture. The changes in the shape of the beta dispersion, which are associated with changes in cell state, are quantified by applying a novel “area ratio” (AR) metric to frequency-scanning data from the dielectric-spectroscopy probes. The AR metric is then used to relate the shape of the beta dispersion to single-frequency permittivity measurements to accurately predict the offline VCV throughout an entire fed-batch run, regardless of cell state. This work demonstrates the possible feasibility of quantifying the shape of the beta dispersion, determined from frequency-scanning data, for enhanced measurement of VCV in mammalian cell cultures by applying a novel shape-characterization technique. In addition, this work demonstrates the utility of using changes in the shape of the beta dispersion to quantify cell health. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 30:479–487, 2014 PMID:24851255

The effect of the processing and formulation parameters on the size of nanoparticles based on block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide) with and without hydrolytically sensitive groups.

PubMed

Neradovic, D; Soga, O; Van Nostrum, C F; Hennink, W E

2004-05-01

Block copolymers of poly(ethylene glycol) (PEG) as a hydrophilic block and N-isopropylacrylamide (PNIPAAm) or poly (NIPAAm-co-N-(2-hydroxypropyl) methacrylamide-dilactate) (poly(NIPAAm-co-HPMAm-dilactate)) as a thermosensitive block, are able to self-assemble in water into nanoparticles above the cloud point (CP) of the thermosensitive block. The influence of processing and the formulation parameters on the size of the nanoparticles was studied using dynamic light scattering. PNIPAAm-b-PEG 2000 polymers were not suitable for the formation of small and stable particles. Block copolymers with PEG 5000 and 10000 formed relatively small and stable particles in aqueous solutions at temperatures above the CP of the thermosensitive block. Their size decreased with increasing molecular weight of the thermosensitive block, decreasing polymer concentration and using water instead of phosphate buffered saline as solvent. Extrusion and ultrasonication were inefficient methods to size down the polymeric nanoparticles. The heating rate of the polymer solutions was a dominant factor for the size of the nanoparticles. When an aqueous polymer solution was slowly heated through the CP, rather large particles (> or = 200 nm) were formed. Regardless the polymer composition, small nanoparticles (50-70 nm) with a narrow size distribution were formed, when a small volume of an aqueous polymer solution below the CP was added to a large volume of heated water. In this way the thermosensitive block copolymers rapidly pass their CP ('heat shock' procedure), resulting in small and stable nanoparticles.

Gonadotrophin-releasing hormone agonist combined with high-intensity focused ultrasound ablation for adenomyosis: a clinical study.

PubMed

Guo, Y; Duan, H; Cheng, J; Zhang, Y

2017-08-01

This study was to investigate the clinical efficacy of a gonadotrophin-releasing hormone agonist (GnRH-a) combined with high-intensity focused ultrasound (HIFU) ablation treatment for adenomyosis. A non-randomized prospective study. Gynaecological Minimally Invasive Centre in a single hospital. Patients with adenomyosis. Seventy-nine patients with adenomyosis were enrolled, including 55 patients in the control group treated with only HIFU and 24 patients in the study group treated with GnRH-a combined with HIFU. All the patients follow up 6 months after the HIFU procedure. The related parameters in the two groups were assessed before and 3 months as well as 6 months after treatment including serum levels of tumor marker and cytokine, volumes of uterine, adenomyotic lesion, and menstrual blood, as well as dysmenorrheal scores. Differences between the group treated with HIFU alone and the group treated with GnRH-a combined with HIFU. Before HIFU treatment, no significant difference was observed in serum levels of CA125, CA19-9, and interleukin-6 (IL-6), the volumes of uterine, adenomyotic lesion, and menstrual blood, as well as dysmenorrhea scores between the two groups. (P > 0.05). The serum CA125 levels significantly decreased in both groups after HIFU, but the serum CA125 levels in the study group were still significantly lower than those in the control group (P < 0.05). The volume of uterine and adenomyotic lesion significantly decreased in both groups after HIFU procedure, and decreased even more in the study group 3 and 6 months after treatment (P < 0.05). Dysmenorrhea scores and menstruation volumes significantly decreased in both groups after HIFU treatment. Moreover in the study group were significantly lower than those in the control group after 3 and 6 months (P < 0.05). No significant difference was observed in the rate of adverse effects between the two groups. The short-term follow-up results indicate that the combination of GnRH-a and HIFU treatment significantly decreased serum CA125 levels, volumes of uterine, adenomyotic lesion and menstrual blood, as well as dysmenorrhea scores, and improved the clinical outcomes compared with the HIFU ablation alone in patients with adenomyosis. However, the further follow-up is needed to explore the long-term effects. A combination of GnRH-a with HIFU in the treatment of adenomyosis significantly decreased serum CA125 levels, uterine and adenomyotic lesion volumes, dysmenorrhea scores, and menstrual blood volumes. © 2017 Royal College of Obstetricians and Gynaecologists.

Three-dimensional histology: tools and application to quantitative assessment of cell-type distribution in rabbit heart

PubMed Central

Burton, Rebecca A.B.; Lee, Peter; Casero, Ramón; Garny, Alan; Siedlecka, Urszula; Schneider, Jürgen E.; Kohl, Peter; Grau, Vicente

2014-01-01

Aims Cardiac histo-anatomical organization is a major determinant of function. Changes in tissue structure are a relevant factor in normal and disease development, and form targets of therapeutic interventions. The purpose of this study was to test tools aimed to allow quantitative assessment of cell-type distribution from large histology and magnetic resonance imaging- (MRI) based datasets. Methods and results Rabbit heart fixation during cardioplegic arrest and MRI were followed by serial sectioning of the whole heart and light-microscopic imaging of trichrome-stained tissue. Segmentation techniques developed specifically for this project were applied to segment myocardial tissue in the MRI and histology datasets. In addition, histology slices were segmented into myocytes, connective tissue, and undefined. A bounding surface, containing the whole heart, was established for both MRI and histology. Volumes contained in the bounding surface (called ‘anatomical volume’), as well as that identified as containing any of the above tissue categories (called ‘morphological volume’), were calculated. The anatomical volume was 7.8 cm3 in MRI, and this reduced to 4.9 cm3 after histological processing, representing an ‘anatomical’ shrinkage by 37.2%. The morphological volume decreased by 48% between MRI and histology, highlighting the presence of additional tissue-level shrinkage (e.g. an increase in interstitial cleft space). The ratio of pixels classified as containing myocytes to pixels identified as non-myocytes was roughly 6:1 (61.6 vs. 9.8%; the remaining fraction of 28.6% was ‘undefined’). Conclusion Qualitative and quantitative differentiation between myocytes and connective tissue, using state-of-the-art high-resolution serial histology techniques, allows identification of cell-type distribution in whole-heart datasets. Comparison with MRI illustrates a pronounced reduction in anatomical and morphological volumes during histology processing. PMID:25362175

Structural imaging of the brain reveals decreased total brain and total gray matter volumes in obese but not in lean women with polycystic ovary syndrome compared to body mass index-matched counterparts.

PubMed

Ozgen Saydam, Basak; Has, Arzu Ceylan; Bozdag, Gurkan; Oguz, Kader Karli; Yildiz, Bulent Okan

2017-07-01

To detect differences in global brain volumes and identify relations between brain volume and appetite-related hormones in women with polycystic ovary syndrome (PCOS) compared to body mass index-matched controls. Forty subjects participated in this study. Cranial magnetic resonance imaging and measurements of fasting ghrelin, leptin and glucagon-like peptide 1 (GLP-1), as well as GLP-1 levels during mixed-meal tolerance test (MTT), were performed. Total brain volume and total gray matter volume (GMV) were decreased in obese PCOS compared to obese controls (p < 0.05 for both) whereas lean PCOS and controls did not show a significant difference. Secondary analyses of regional brain volumes showed decreases in GMV of the caudate nucleus, ventral diencephalon and hippocampus in obese PCOS compared to obese controls (p < 0.05 for all), whereas lean patients with PCOS had lower GMV in the amygdala than lean controls (p < 0.05). No significant relations were detected between structural differences and measured hormone levels at baseline or during MTT. This study, investigating structural brain alterations in PCOS, suggests volumetric reductions in global brain areas in obese women with PCOS. Functional studies with larger sample size are needed to determine physiopathological roles of these changes and potential effects of long-term medical management on brain structure of PCOS.

Microstructure and hydrogenation properties of a melt-spun non-stoichiometric Zr-based Laves phase alloy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Tiebang, E-mail: tiebangzhang@nwpu.edu.cn; Zhang, Yunlong; Li, Jinshan

2016-01-15

Alloy with composition of Zr{sub 0.9}Ti{sub 0.1}V{sub 1.7} off normal stoichiometric proportion is selected to investigate the effect of defects introduced by non-stoichiometry on hydrogenation kinetics of Zr–Ti–V Laves phase alloys. Microstructure and phase constituent of melt-spun ribbons have been investigated in this work. The activation process, hydrogenation kinetics, thermodynamics characteristics and hydride phase constituent of as-cast alloy and melt-spun ribbons are also compared. Comparing with the as-cast alloy, the dominant Laves phase ZrV{sub 2} is preserved, V-BCC phase is reduced and α-Zr phase is replaced by a small amount of Zr{sub 3}V{sub 3}O phase in melt-spun ribbons. Melt-spun ribbonsmore » exhibit easy activation and fast initial hydrogen absorption on account of the increased specific surface area. However, the decrease in unit cell volume of the dominant phase leads to the decrease in hydrogen absorption capacity. Melt-spinning technique raises the equilibrium pressure and decreases the stability of hydride due to the decrease of unit cell volume and the elimination of α-Zr phase, respectively. Melt-spun ribbons with fine grains show improved hydrogen absorption kinetics comparing with that of the as-cast alloy. Meanwhile, the prevalent micro twins observed within melt-spun ribbons are believed to account for the improved hydrogen absorption kinetics. - Highlights: • Role of defects on hydrogenation kinetics of Zr-based alloys is proposed. • Microstructure and hydrogenation properties of as-cast/melt-spun alloy are compared. • Melt-spinning technique improves the hydrogenation kinetics of Zr{sub 0.9}Ti{sub 0.1}V{sub 1.7} alloy. • Refined grains and twin defects account for improved hydrogen absorption kinetics.« less

Effects of Human Activities on Submarine Topography in Lingding Bay of the Pearl River Estuary During the Last Decade

NASA Astrophysics Data System (ADS)

WU, Z. Y.; Saito, Y.; Milliman, J. D.; Zhao, D.; Zhou, J.

2015-12-01

Estuaries have been the site of intensive human activities. During the past century, decreased fluvial water and sediment discharge, increasing land reclamation, changing climate, and rising sea level have had an ever-increasing impact on river deltas, particularly those deltas bordering Southeast Asia. Using six stages of navigational and bathymetric chart data from 1906 to 2013 and 2 years (2012,2013) single-beam bathymetric data, together with more than 50 years of fluvial discharge data, we document the impact of human activities on the Pearl River Delta and its estuary at Lingding Bay. Between 1906 and 2010, land reclamation decreased the bay's water area by ~300 km2 (>17%), mostly at the expense of the shrinking intertidal and shallow subtidal mudflats. Before 1980, the estuary was mainly governed by natural processes with slight net deposition, whereas after 1980 dredging in the estuary and large port engineering projects changed the estuarine topography by shallowing the shoals and deepening the troughs. From 1955 to 2010, the water volume of Lingding Bay decreased by 536 × 106 m3 for a net decrease of 9.7 × 106 m3 a year, which indicates that approximately 9.7 Mt/yr of sediment was deposited in Lingding Bay during that period. In 2012 and 2013, large-scale human activities within Lingding Bay included continued dredging plus a surge of sand excavation that changed local water depths by ±5 m/yr, far exceeding the range of natural topographic evolution in the estuary. The impacts of various human activities have significantly changed submarine topography in Lingding Bay of the complex Pearl River Estuary. With continuing economic expansion in the Pearl River Delta, Lingding Bay should continue to shrink in both area and water volume.

Auto-recognition of surfaces and auto-generation of material removal volume for finishing process

NASA Astrophysics Data System (ADS)

Kataraki, Pramod S.; Salman Abu Mansor, Mohd

2018-03-01

Auto-recognition of a surface and auto-generation of material removal volumes for the so recognised surfaces has become a need to achieve successful downstream manufacturing activities like automated process planning and scheduling. Few researchers have contributed to generation of material removal volume for a product but resulted in material removal volume discontinuity between two adjacent material removal volumes generated from two adjacent faces that form convex geometry. The need for limitation free material removal volume generation was attempted and an algorithm that automatically recognises computer aided design (CAD) model’s surface and also auto-generate material removal volume for finishing process of the recognised surfaces was developed. The surfaces of CAD model are successfully recognised by the developed algorithm and required material removal volume is obtained. The material removal volume discontinuity limitation that occurred in fewer studies is eliminated.

Early Change in Stroke Size Performs Best in Predicting Response to Therapy.

PubMed

Simpkins, Alexis Nétis; Dias, Christian; Norato, Gina; Kim, Eunhee; Leigh, Richard

2017-01-01

Reliable imaging biomarkers of response to therapy in acute stroke are needed. The final infarct volume and percent of early reperfusion have been used for this purpose. Early fluctuation in stroke size is a recognized phenomenon, but its utility as a biomarker for response to therapy has not been established. This study examined the clinical relevance of early change in stroke volume and compared it with the final infarct volume and percent of early reperfusion in identifying early neurologic improvement (ENI). Acute stroke patients, enrolled between 2013 and 2014 with serial magnetic resonance imaging (MRI) scans (pretreatment baseline, 2 h post, and 24 h post), who received thrombolysis were included in the analysis. Early change in stroke volume, infarct volume at 24 h on diffusion, and percent of early reperfusion were calculated from the baseline and 2 h MRI scans were compared. ENI was defined as ≥4 point decrease in National Institutes of Health Stroke Scales within 24 h. Logistic regression models and receiver operator characteristics analysis were used to compare the efficacy of 3 imaging biomarkers. Serial MRIs of 58 acute stroke patients were analyzed. Early change in stroke volume was significantly associated with ENI by logistic regression analysis (OR 0.93, p = 0.048) and remained significant after controlling for stroke size and severity (OR 0.90, p = 0.032). Thus, for every 1 mL increase in stroke volume, there was a 10% decrease in the odds of ENI, while for every 1 mL decrease in stroke volume, there was a 10% increase in the odds of ENI. Neither infarct volume at 24 h nor percent of early reperfusion were significantly associated with ENI by logistic regression. Receiver-operator characteristic analysis identified early change in stroke volume as the only biomarker of the 3 that performed significantly different than chance (p = 0.03). Early fluctuations in stroke size may represent a more reliable biomarker for response to therapy than the more traditional measures of final infarct volume and percent of early reperfusion. © 2017 S. Karger AG, Basel.

Evaluation of parameters related to libido and semen quality in Zebu bulls naturally infected with Trypanosoma vivax.

PubMed

Bittar, Joely F F; Bassi, Paula B; Moura, Dênia M; Garcia, Guilherme C; Martins-Filho, Olindo Assis; Vasconcelos, André B; Costa-Silva, Matheus F; Barbosa, Cristiano P; Araújo, Márcio S S; Bittar, Eustáquio R

2015-10-14

Trypanosomiasis is a disease caused by Trypanosoma (Dutonella) vivax, a hemoprotozoa that can affect bovines. In South America, the sanguineous form is mechanically transmitted from one mammalian host (ruminant) to another by the bite of a blood-sucking insect or by needles contaminated with infected blood. The negative impact of the parasitosis caused by T. vivax infection on the reproductive activity of male and female ruminants is known to reduce fertility. In males, alterations such as degeneration, diffuse or interlobular inflammatory infiltrate found in ovine and bovine testicles, can affect fertility through decreased sperm quality. This study evaluated the impact of natural infection with T. vivax on Zebu bulls from the Central Station of Artificial Insemination (CSAI) with regard to libido and the negative effects caused by this protozoan on semen quality. Blood samples of 44 animals were collected to evaluate the presence of the trypomastigote form of T. vivax in blood smears obtained from hematocrit and buffy coat, and antibody titer IgG anti T. vivax in indirect Immunoflorescence (IFI). Furthermore, data related to libido, ejaculate volume, spermatic concentration, and seminal vigor were recorded for these animals employing the criteria of the CSAI. Nine animals (20.45 %) showed T. vivax trypomastigotes and parasitemia between 0.02 and 0.07, and antibody titers from 1:80 to 1:320 in IFI. Twenty nine negative animals in parasitological tests were not reactive in IFI, and six animals presented the antibodies IgG anti T. vivax in IFI. Data on reproductive activity showed that animals infected with T. vivax have a decreased libido and an increased spermatic volume, whereas other factors related to the reproductive process such as spermatic concentration, motility and spermatic force, were unchanged in infected bulls. The T. vivax infection in Zebu bulls from CSAI caused patent parasitemia, induced a febrile state, promoted reduction in the libido and increased the ejaculate volume. These conditions together may account to decrease the performance of these animals.

Evaluation of the effect of prostate volume change on tumor control probability in LDR brachytherapy.

PubMed

Knaup, Courtney; Mavroidis, Panayiotis; Stathakis, Sotirios; Smith, Mark; Swanson, Gregory; Papanikolaou, Niko

2011-09-01

This study evaluates low dose-rate brachytherapy (LDR) prostate plans to determine the biological effect of dose degradation due to prostate volume changes. In this study, 39 patients were evaluated. Pre-implant prostate volume was determined using ultrasound. These images were used with the treatment planning system (Nucletron Spot Pro 3.1(®)) to create treatment plans using (103)Pd seeds. Following the implant, patients were imaged using CT for post-implant dosimetry. From the pre and post-implant DVHs, the biologically equivalent dose and the tumor control probability (TCP) were determined using the biologically effective uniform dose. The model used RBE = 1.75 and α/β = 2 Gy. The prostate volume changed between pre and post implant image sets ranged from -8% to 110%. TCP and the mean dose were reduced up to 21% and 56%, respectively. TCP is observed to decrease as the mean dose decreases to the prostate. The post-implant tumor dose was generally observed to decrease, compared to the planned dose. A critical uniform dose of 130 Gy was established. Below this dose, TCP begins to fall-off. It was also determined that patients with a small prostates were more likely to suffer TCP decrease. The biological effect of post operative prostate growth due to operative trauma in LDR was evaluated using the concept. The post-implant dose was lower than the planned dose due to an increase of prostate volume post-implant. A critical uniform dose of 130 Gy was determined, below which TCP begun to decline.

Creep deformation in near-γ TiAl: Part 1. the influence of microstructure on creep deformation in Ti-49Al-1V

NASA Astrophysics Data System (ADS)

Worth, Brian D.; Jones, J. Wayne; Allison, John E.

1995-11-01

The influence of microstructure on creep deformation was examined in the near-y TiAl alloy Ti-49A1-1V. Specifically, microstructures with varying volume fractions of lamellar constituent were produced through thermomechanical processing. Creep studies were conducted on these various microstructures under constant load in air at temperatures between 760 °C and 870 °C and at stresses ranging from 50 to 200 MPa. Microstructure significantly influences the creep behavior of this alloy, with a fully lamellar microstructure yielding the highest creep resistance of the microstructures examined. Creep resistance is dependent on the volume fraction of lamellar constituent, with the lowest creep resistance observed at intermediate lamellar volume fractions. Examination of the creep deformation structure revealed planar slip of dislocations in the equiaxed y microstructure, while subboundary formation was observed in the duplex microstructure. The decrease in creep resistance of the duplex microstructure, compared with the equiaxed y microstructure, is attributed to an increase in dislocation mobility within the equiaxed y constituent, that results from partitioning of oxygen from the γ phase to the α2 phase. Dislocation motion in the fully lamellar microstructure was confined to the individual lamellae, with no evidence of shearing of γ/γ or γ/α2 interfaces. This suggests that the high creep resistance of the fully lamellar microstructure is a result of the fine spacing of the lamellar structure, which results in a decreased effective slip length for dislocation motion over that found in the duplex and equiaxed y microstructures.

Decrease of pulmonary blood flow detected by phase contrast MRI is correlated with a decrease in lung volume and increase of lung fibrosis area determined by computed tomography in interstitial lung disease.

PubMed

Tsuchiya, Nanae; Yamashiro, Tsuneo; Murayama, Sadayuki

2016-09-01

Lung volume and pulmonary blood flow decrease in patients with interstitial lung disease (ILD). The purpose of this study was to assess the relationship between pulmonary blood flow and lung volume in ILD patients. This research was approved by the institutional review board. Twenty-seven patients (9 men, 18 women; mean age, 59 years; range, 24-79 years) with ILD were included. Blood flow was assessed in the pulmonary trunk and the left and right pulmonary arteries by phase contrast magnetic resonance imaging (MRI). Lung volume and the computed tomography (CT) visual score that indicates the severity of ILD were assessed on the left and right sides by thin-section CT scanning. Lung volume was automatically measured by lung analysis software (VINCENT Ver. 4). The CT visual score was measured by averaging the proportion of abnormal lung area at five anatomic levels. Pearson's correlation coefficient was used to determine the relationship between pulmonary blood flow and lung volume. Pulmonary blood flow showed a significant correlation with lung volume (both: r=0.52, p=0.006; left: r=0.61, p=0.001; right: r=0.54, p=0.004) and CT visual score (both: r=-0.39, p=0.04; left: r=-0.48, p=0.01; right: r=-0.38, p=0.04). Partial correlation analysis, controlled for age, height and weight, showed a significant correlation between pulmonary blood flow and lung volume (both: r=0.43, p=0.03; left: r=0.55, p=0.005; right: r=0.48, p=0.01) and CT visual score (both: r=-0.58, p=0.003; left: r=-0.51, p=0.01; right: r=-0.64, p=0.001). In ILD, reduced pulmonary blood flow is associated with reduced lung volume and increased abnormal lung area. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Fluid displacement from intraluminal thrombus of abdominal aortic aneurysm as a result of uniform compression.

PubMed

van Noort, Kim; Schuurmann, Richte Cl; Wermelink, Bryan; Slump, Cornelis H; Kuijpers, Karel C; de Vries, Jean-Paul Pm

2017-10-01

Objectives The results after aneurysm repair with an endovascular aneurysm sealing (EVAS) system are dependent on the stability of the aneurysm sac and particularly the intraluminal abdominal aortic thrombus (ILT). The postprocedural ILT volume is decreased compared with preprocedural ILT volume in aortic aneurysm patients treated with EVAS. We hypothesize that ILT is not stable in all patients and pressurization of the ILT may result in displacement of fluids from the ILT, no differently than serum is displaced from whole blood when it settles. To date, the mechanism and quantification of fluid displacement from ILT are unknown. Methods The study included 21 patients who underwent elective open abdominal aortic aneurysm repair. The ILT was harvested as a routine procedure during the operation. After excision of a histologic sample of the ILT specimen in four patients, ILT volume was measured and the ILT was compressed in a dedicated compression setup designed to apply uniform compression of 200 mmHg for 5 min. After compression, the volumes of the remaining thrombus and the displaced fluid were measured. Results The median (interquartile-range) of ILT volume before compression was 60 (66) mL, and a median of 5.7 (8.4) mL of fluid was displaced from the ILT after compression, resulting in a median thrombus volume decrease of 11% (10%). Fluid components can be up to 31% of the entire ILT volume. Histologic examination of four ILT specimens showed a reduction of the medial layer of the ILT after compression, which was the result of compression of fluid-containing canaliculi. Conclusions Applying pressure of 200 mmHg to abdominal aortic aneurysm ILT resulted in the displacement of fluid, with a large variation among patients. Fluid displacement may result in decrease of ILT volume during and after EVAS, which might have implications on pre-EVAS volume planning and on stability of the endobags during follow-up which may lead to migration, endoleak or both.

Dehydration, hemodynamics and fluid volume optimization after induction of general anesthesia.

PubMed

Li, Yuhong; He, Rui; Ying, Xiaojiang; Hahn, Robert G

2014-01-01

Fluid volume optimization guided by stroke volume measurements reduces complications of colorectal and high-risk surgeries. We studied whether dehydration or a strong hemodynamic response to general anesthesia increases the probability of fluid responsiveness before surgery begins. Cardiac output, stroke volume, central venous pressure and arterial pressures were measured in 111 patients before general anesthesia (baseline), after induction and stepwise after three bolus infusions of 3 ml/kg of 6% hydroxyethyl starch 130/0.4 (n=86) or Ringer's lactate (n=25). A subgroup of 30 patients who received starch were preloaded with 500 ml of Ringer's lactate. Blood volume changes were estimated from the hemoglobin concentration and dehydration was estimated from evidence of renal water conservation in urine samples. Induction of anesthesia decreased the stroke volume to 62% of baseline (mean); administration of fluids restored this value to 84% (starch) and 68% (Ringer's). The optimized stroke volume index was clustered around 35-40 ml/m2/beat. Additional fluid boluses increased the stroke volume by ≥10% (a sign of fluid responsiveness) in patients with dehydration, as suggested by a low cardiac index and central venous pressure at baseline and by high urinary osmolality, creatinine concentration and specific gravity. Preloading and the hemodynamic response to induction did not correlate with fluid responsiveness. The blood volume expanded 2.3 (starch) and 1.8 (Ringer's) times over the infused volume. Fluid volume optimization did not induce a hyperkinetic state but ameliorated the decrease in stroke volume caused by anesthesia. Dehydration, but not the hemodynamic response to the induction, was correlated with fluid responsiveness.

Specificity of abnormal brain volume in major depressive disorder: a comparison with borderline personality disorder.

PubMed

Depping, Malte S; Wolf, Nadine D; Vasic, Nenad; Sambataro, Fabio; Thomann, Philipp A; Christian Wolf, R

2015-03-15

Abnormal brain volume has been frequently demonstrated in major depressive disorder (MDD). It is unclear if these findings are specific for MDD since aberrant brain structure is also present in disorders with depressive comorbidity and affective dysregulation, such as borderline personality disorder (BPD). In this transdiagnostic study, we aimed to investigate if regional brain volume loss differentiates between MDD and BPD. Further, we tested for associations between brain volume and clinical variables within and between diagnostic groups. 22 Females with a DSM-IV diagnosis of MDD, 17 females with a DSM-IV diagnosis of BPD and without comorbid posttraumatic stress disorder, and 22 age-matched female healthy controls (HC) were investigated using magnetic resonance imaging. High-resolution structural data were analyzed using voxel-based morphometry. A significant (p<0.05, cluster-corrected) volume decrease of the anterior cingulate cortex (ACC) was found in MDD compared to HC, as opposed to volume decreases of the amygdala in BPD compared to both HC and MDD. Sensitivity and specificity of regional gray matter volume for a diagnosis of MDD were modest to fair. Amygdala volume was related to depressive symptoms across the entire patient sample. Potential limitations of this study include the modest sample size and the heterogeneous psychotropic drug treatment. ACC volume reduction is more pronounced in MDD with an intermediate degree of volume loss in BPD compared to HC. In contrast, amygdala volume loss is more pronounced in BPD compared to MDD, yet amygdala volume is associated with affective symptom expression in both disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

Roles of Polyuria and Hyperglycemia on Bladder Dysfunction in Diabetes

PubMed Central

Xiao, Nan; Wang, Zhiping; Huang, Yexiang; Daneshgari, Firouz; Liu, Guiming

2014-01-01

Purpose Diabetes mellitus (DM) causes diabetic bladder dysfunction (DBD). We aimed to identify the pathogenic roles of polyuria and hyperglycemia on DBD in rats. Materials and Methods Seventy-two female Sprague-Dawley rats were divided: age-matched controls (control), sham urinary diversion (sham), urinary diversion (UD), streptozotocin-induced diabetes after sham UD (DM), streptozotocin-induced diabetes after UD (UD+DM), and 5% sucrose-induced diuresis after sham UD (DIU). UD was performed by ureterovaginostomy 10d before DM induction. Animals were evaluated 20 wks after DM or diuresis induction. We measured 24-hr drinking and voiding volumes and cystometry (CMG). Bladders were harvested for quantification of smooth muscle, urothelium, and collagen. We measured nitrotyrosine and manganese superoxide dismutase (MnSOD) in bladder. Results Diabetes and diuresis caused increases in drinking volume, voiding volume and bladder weight. Bladder weights decreased in the UD and UD+DM groups. Intercontractile intervals, voided volume, and compliance increased in the DIU and DM groups, decreased in the UD, and further decreased in the UD+DM group. The total cross-sectional tissue, smooth muscle and urothelium areas increased in the DIU and DM groups, and decreased in the UD and UD+DM groups. As percentages of total tissue area, collagen decreased in the DIU and DM groups, and increased in the UD and UD+DM groups, and smooth muscle and urothelium decreased in the UD and UD+DM groups. Nitrotyrosine and MnSOD increased in DM and UD+DM rats. Conclusions Polyuria induced bladder hypertrophy, while hyperglycemia induced substantial oxidative stress in the bladder, which may play a pathogenic role in late stage DBD. PMID:22999997

Annealing properties of open volumes in HfSiOx and HfAlOx gate dielectrics studied using monoenergetic positron beams

NASA Astrophysics Data System (ADS)

Uedono, A.; Ikeuchi, K.; Yamabe, K.; Ohdaira, T.; Muramatsu, M.; Suzuki, R.; Hamid, A. S.; Chikyow, T.; Torii, K.; Yamada, K.

2005-07-01

Thin Hf0.6Si0.4Ox and Hf0.3Al0.7Ox films fabricated by metal-organic chemical-vapor deposition and atomic-layer-deposition techniques were characterized using monoenergetic positron beams. Measurements of the Doppler broadening spectra of annihilation radiation and the lifetime spectra of positions indicated that positrons annihilated from the trapped state by open volumes that exist intrinsically in amorphous structures of the films. For HfSiOx, the mean size of the open volumes and their size distribution decreased with increasing postdeposition annealing (PDA) temperature. For HfAlOx, although the overall behavior of the open volumes in response to annealing was similar to that for HfSiOx, PDA caused a separation of the mean size of the open volumes. When this separation occurred, the value of the line-shape parameter S increased, suggesting an oxygen deficiency in the amorphous matrix. This fragmentation of the amorphous matrix can be suppressed by decreasing the annealing time.

Statistical Mechanical Proof of the Second Law of Thermodynamics based on Volume Entropy

NASA Astrophysics Data System (ADS)

Campisi, Michele

2007-10-01

As pointed out in [M. Campisi. Stud. Hist. Phil. M. P. 36 (2005) 275-290] the volume entropy (that is the logarithm of the volume of phase space enclosed by the constant energy hyper-surface) provides a good mechanical analogue of thermodynamic entropy because it satisfies the heat theorem and it is an adiabatic invariant. This property explains the ``equal'' sign in Clausius principle (Sf>=Si) in a purely mechanical way and suggests that the volume entropy might explain the ``larger than'' sign (i.e. the Law of Entropy Increase) if non adiabatic transformations were considered. Based on the principles of quantum mechanics here we prove that, provided the initial equilibrium satisfy the natural condition of decreasing ordering of probabilities, the expectation value of the volume entropy cannot decrease for arbitrary transformations performed by some external sources of work on a insulated system. This can be regarded as a rigorous quantum mechanical proof of the Second Law.

Longitudinal brain MRI study in a mouse model of Rett Syndrome and the effects of choline.

PubMed

Ward, B C; Agarwal, S; Wang, K; Berger-Sweeney, J; Kolodny, N H

2008-07-01

Rett Syndrome (RTT), the second most common cause of mental retardation in girls, is associated with mutations of an X-linked gene encoding the transcriptional repressor protein MeCP2. Mecp2(1lox) mutant mice express no functional MeCP2 protein and exhibit behavioral abnormalities similar to those seen in RTT patients. Here we monitor the development of both whole brain and regional volumes between 21 and 42 days of age in this model of RTT using MRI. We see decreases in whole brain volumes in both male and female mutant mice. Cerebellar and ventricular volumes are also decreased in RTT males. Previous work has suggested that perinatal choline supplementation alleviates some of the behavioral deficits in both male and female Mecp2(1lox) mutant mice. Here we show that perinatal choline supplementation also positively affects whole brain volume in heterozygous females, and cerebellar volume in male RTT mice.

Increased Testosterone Decreases Medial Cortical Volume and Neurogenesis in Territorial Side-Blotched Lizards (Uta stansburiana)

PubMed Central

LaDage, Lara D.; Roth, Timothy C.; Downs, Cynthia J.; Sinervo, Barry; Pravosudov, Vladimir V.

2017-01-01

Variation in an animal's spatial environment can induce variation in the hippocampus, an area of the brain involved in spatial cognitive processing. Specifically, increased spatial area use is correlated with increased hippocampal attributes, such as volume and neurogenesis. In the side-blotched lizard (Uta stansburiana), males demonstrate alternative reproductive tactics and are either territorial—defending large, clearly defined spatial boundaries—or non-territorial—traversing home ranges that are smaller than the territorial males' territories. Our previous work demonstrated cortical volume (reptilian hippocampal homolog) correlates with these spatial niches. We found that territorial holders have larger medial cortices than non-territory holders, yet these differences in the neural architecture demonstrated some degree of plasticity as well. Although we have demonstrated a link among territoriality, spatial use, and brain plasticity, the mechanisms that underlie this relationship are unclear. Previous studies found that higher testosterone levels can induce increased use of the spatial area and can cause an upregulation in hippocampal attributes. Thus, testosterone may be the mechanistic link between spatial area use and the brain. What remains unclear, however, is if testosterone can affect the cortices independent of spatial experiences and whether testosterone differentially interacts with territorial status to produce the resultant cortical phenotype. In this study, we compared neurogenesis as measured by the total number of doublecortin-positive cells and cortical volume between territorial and non-territorial males supplemented with testosterone. We found no significant differences in the number of doublecortin-positive cells or cortical volume among control territorial, control non-territorial, and testosterone-supplemented non-territorial males, while testosterone-supplemented territorial males had smaller medial cortices containing fewer doublecortin-positive cells. These results demonstrate that testosterone can modulate medial cortical attributes outside of differential spatial processing experiences but that territorial males appear to be more sensitive to alterations in testosterone levels compared with non-territorial males. PMID:28298883

[Aging of the respiratory system: anatomical changes and physiological consequences].

PubMed

Ketata, W; Rekik, W K; Ayadi, H; Kammoun, S

2012-10-01

The respiratory system undergoes progressive involution with age, resulting in anatomical and functional changes that are exerted on all levels. The rib cage stiffens and respiratory muscles weaken. Distal bronchioles have reduced diameter and tend to be collapsed. Mobilized lung volumes decrease with age while residual volume increases. Gas exchanges are modified with a linear decrease of PaO(2) up to the age of 70 years and a decreased diffusing capacity of carbon monoxide. Ventilatory responses to hypercapnia, hypoxia and exercise decrease in the elderly. Knowledge of changes in the respiratory system related to advancing age is a medical issue of great importance in order to distinguish the effects of aging from those of diseases. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Multimodal MR-imaging reveals large-scale structural and functional connectivity changes in profound early blindness

PubMed Central

Bauer, Corinna M.; Hirsch, Gabriella V.; Zajac, Lauren; Koo, Bang-Bon; Collignon, Olivier

2017-01-01

In the setting of profound ocular blindness, numerous lines of evidence demonstrate the existence of dramatic anatomical and functional changes within the brain. However, previous studies based on a variety of distinct measures have often provided inconsistent findings. To help reconcile this issue, we used a multimodal magnetic resonance (MR)-based imaging approach to provide complementary structural and functional information regarding this neuroplastic reorganization. This included gray matter structural morphometry, high angular resolution diffusion imaging (HARDI) of white matter connectivity and integrity, and resting state functional connectivity MRI (rsfcMRI) analysis. When comparing the brains of early blind individuals to sighted controls, we found evidence of co-occurring decreases in cortical volume and cortical thickness within visual processing areas of the occipital and temporal cortices respectively. Increases in cortical volume in the early blind were evident within regions of parietal cortex. Investigating white matter connections using HARDI revealed patterns of increased and decreased connectivity when comparing both groups. In the blind, increased white matter connectivity (indexed by increased fiber number) was predominantly left-lateralized, including between frontal and temporal areas implicated with language processing. Decreases in structural connectivity were evident involving frontal and somatosensory regions as well as between occipital and cingulate cortices. Differences in white matter integrity (as indexed by quantitative anisotropy, or QA) were also in general agreement with observed pattern changes in the number of white matter fibers. Analysis of resting state sequences showed evidence of both increased and decreased functional connectivity in the blind compared to sighted controls. Specifically, increased connectivity was evident between temporal and inferior frontal areas. Decreases in functional connectivity were observed between occipital and frontal and somatosensory-motor areas and between temporal (mainly fusiform and parahippocampus) and parietal, frontal, and other temporal areas. Correlations in white matter connectivity and functional connectivity observed between early blind and sighted controls showed an overall high degree of association. However, comparing the relative changes in white matter and functional connectivity between early blind and sighted controls did not show a significant correlation. In summary, these findings provide complimentary evidence, as well as highlight potential contradictions, regarding the nature of regional and large scale neuroplastic reorganization resulting from early onset blindness. PMID:28328939

Hematology, blood typing, and immunology of the neonatal foal.

PubMed

Becht, J L; Semrad, S D

1985-04-01

Hematologic parameters change during the first 10 days of life. Erythrocytes increase in number but decrease in size and hemoglobin concentration. The PCV, hemoglobin, and platelet count also decrease. Total blood and plasma volume and, to lesser extent, erythrocyte volume decrease. Normal neonatal foals may have immature neutrophils (up to 5 per cent bands), and their early rapid rise in neutrophil numbers may be accompanied by a lymphopenia. Monocytes, eosinophils, and basophils are all absent or low initially. Infectious processes can cause rapid and variable changes in the leukogram. However, elevation of fibrinogen levels may lag behind the development of an inflammatory process, and this parameter should not be relied on for early evidence of infection. After 12 hours of life, there is generally a decrease in serum concentrations of Na, Cl, iron, creatinine, BUN, plasma protein, and possibly calcium. LDH, SAP, P, bilirubin, and glucose concentrations are all higher in foals than in mature horses. Creatinine may actually be elevated during the first 12 hours of life and then decreases. If azotemia, hypochloremia, hyponatremia, and hyperkalemia are found, ruptured bladder with uroperitoneum should be suspected. The creatinine concentration is preferable to BUN determination for diagnosis of this condition. Blood typing is useful for diagnosis of NI, determination of blood compatability between donor and transfusion recipient, and for verification of parentage for breed registries. Several techniques are available. Several tests are available for evaluation of the foal's immunoglobulin levels and confirmation of passive antibody transfer. Because foals suffering from FPT are more predisposed to infections, their immunoglobulin status should be determined as early as possible so that additional colostrum or plasma can be administered as needed. Neonatal isoerythrolysis is uncommon but is an important immunologic syndrome that often results in a fatal hemolytic crisis. If one suspects the condition may be likely, the optimal time for testing the mare is during the last 2 weeks of gestation. If the foal's dam is shown to have alloantibodies against a panel of known erythrocyte alloantigens, prevention is possible by feeding colostrum from another mare. If a foal develops NI, further colostrum ingestion from the dam must be prevented. Good nursing care, minimizing stress, and adequate frequent feedings are essential; prophylactic antibiotics should be used, and transfusion may be necessary.

Long-range laser scanning and 3D imaging for the Gneiss quarries survey

NASA Astrophysics Data System (ADS)

Schenker, Filippo Luca; Spataro, Alessio; Pozzoni, Maurizio; Ambrosi, Christian; Cannata, Massimiliano; Günther, Felix; Corboud, Federico

2016-04-01

In Canton Ticino (Southern Switzerland), the exploitation of natural stone, mostly gneisses, is an important activity of valley's economies. Nowadays, these economic activities are menaced by (i) the exploitation costs related to geological phenomena such as fractures, faults and heterogeneous rocks that hinder the processing of the stone product, (ii) continuously changing demand because of the evolving natural stone fashion and (iii) increasing administrative limits and rules acting to protect the environment. Therefore, the sustainable development of the sector for the next decades needs new and effective strategies to regulate and plan the quarries. A fundamental step in this process is the building of a 3D geological model of the quarries to constrain the volume of commercial natural stone and the volume of waste. In this context, we conducted Terrestrial Laser Scanning surveys of the quarries in the Maggia Valley to obtain a detailed 3D topography onto which the geological units were mapped. The topographic 3D model was obtained with a long-range laser scanning Riegl VZ4000 that can measure from up to 4 km of distance with a speed of 147,000 points per second. It operates with the new V-line technology, which defines the surface relief by sensing differentiated signals (echoes), even in the presence of obstacles such as vegetation. Depending on the esthetics of the gneisses, we defined seven types of natural stones that, together with faults and joints, were mapped onto the 3D models of the exploitation sites. According to the orientation of the geological limits and structures, we projected the different rock units and fractures into the excavation front. This way, we obtained a 3D geological model from which we can quantitatively estimate the volume of the seven different natural stones (with different commercial value) and waste (with low commercial value). To verify the 3D geological models and to quantify exploited rock and waste volumes the same procedure will be repeated after ca. 6 months. Finally, these 3D geological models can be useful to (i) decrease the exploitation costs because they yield the extraction potential of quarry, (ii) become more efficient in the exploitation and more dynamic in the market because they permit better planning and (iii) decrease the waste by limiting the excavation in regions with low-quality rocks.

Diffusive dynamics of nanoparticles in ultra-confined media

DOE PAGES

Jacob, Jack Deodato; Conrad, Jacinta; Krishnamoorti, Ramanan; ...

2015-08-10

Differential dynamic microscopy (DDM) was used to investigate the diffusive dynamics of nanoparticles of diameter 200 400 nm that were strongly confined in a periodic square array of cylindrical nanoposts. The minimum distance between posts was 1.3 5 times the diameter of the nanoparticles. The image structure functions obtained from the DDM analysis were isotropic and could be fit by a stretched exponential function. The relaxation time scaled diffusively across the range of wave vectors studied, and the corresponding scalar diffusivities decreased monotonically with increased confinement. The decrease in diffusivity could be described by models for hindered diffusion that accountedmore » for steric restrictions and hydrodynamic interactions. The stretching exponent decreased linearly as the nanoparticles were increasingly confined by the posts. Altogether, these results are consistent with a picture in which strongly confined nanoparticles experience a heterogeneous spatial environment arising from hydrodynamics and volume exclusion on time scales comparable to cage escape, leading to multiple relaxation processes and Fickian but non-Gaussian diffusive dynamics.« less

Intravenous Sedation with Low-Dose Dexmedetomidine: Its Potential for Use in Dentistry

PubMed Central

Ogawa, Sachie; Seino, Hiroaki; Ito, Hiroshi; Yamazaki, Shinya; Ganzberg, Steven; Kawaai, Hiroyoshi

2008-01-01

This study investigated the physiologic and sedative parameters associated with a low-dose infusion of dexmedetomidine (Dex). Thirteen healthy volunteers were sedated with Dex at a loading dose of 6 mcg/kg/h for 5 minutes and a continuous infusion dose of 0.2 mcg/kg/h for 25 minutes. The recovery process was observed for 60 minutes post infusion. The tidal volume decreased significantly despite nonsignificant changes in respiratory rate, minute ventilation, oxygen saturation, and end-tidal carbon dioxide. The mean arterial pressure and heart rate also decreased significantly but within clinically acceptable levels. Amnesia to pin prick was present in 69% of subjects. A Trieger dot test plot error ratio did not show a significant change at 30 minutes post infusion despite a continued significant decrease in bispectral index. We conclude that sedation with a low dose of Dex appears to be safe and potentially efficacious for young healthy patients undergoing dental procedures. PMID:18788843

Influence of cobalt, tantaum and tungsten on the high temperature mechanical properties of single crystal nickel-base superalloys. Ph.D. Thesis - Case Western Reserve Univ.

NASA Technical Reports Server (NTRS)

Nathal, M. V.

1984-01-01

For alloys with the baseline refractory metal level of 3 percent Ta and 10 percent W, decreases in Co level from 10 to 0 percent resulted in increased tensile strength and creep resistance. Substitution of W for Ta resulted in decreased creep life at high stresses but improved life at low stresses. Substitution of Ni for Ta caused large reductions in tensile strength and creep resistance, and corresponding increases in ductility. For these alloys with low Ta plus W totals, strength was independent of Co level. The increases in tensile strength with increases in refractory metal content were related to the increases in gamma volume fraction and solid solution hardening. Increases in strength as Co level decreased were considered to be the result of coherency strain hardening from the increased lattice mismatch. Dislocation shear through the gamma-gamma interface is considered to be the rate limiting step in the deformation process.

Epinephrine and left atrial and left ventricular diastolic function decrease in normal subjects.

PubMed

Fuenmayor, Abdel J; Solórzano, Moisés I; Gómez, Luisangelly

2016-10-01

We assessed the effect of epinephrine over left atrial and left ventricular diastolic function in subjects without structural heart disease. Twenty-seven, 34.6±17.2year-old patients without structural heart disease were included. Intravenous epinephrine (50 to 100ng/kg/min) was infused. Left atrial and ventricular functions were evaluated by means of echocardiography before and during the epinephrine infusion. No complications were observed. Significant increases in heart rate and systolic blood pressure were recorded. Both left atrial (minimal and maximal) volumes increased but increase in the minimal volume was more pronounced, and the ejection fraction diminished. Left atrial expansion index decreased and the fraction of left ventricular inflow volume resulting from atrial contraction increased. Two patients displayed abnormal left ventricular diastolic function. During epinephrine infusion, E/A and e' decreased, and isovolumetric relaxation time increased. In this group of young adults without structural heart disease, epinephrine infusion was safe, did not produce any complications, and induced a small but significant decrease in left atrial function and left ventricular diastolic function. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Flat-plate solar array project. Volume 5: Process development

NASA Technical Reports Server (NTRS)

Gallagher, B.; Alexander, P.; Burger, D.

1986-01-01

The goal of the Process Development Area, as part of the Flat-Plate Solar Array (FSA) Project, was to develop and demonstrate solar cell fabrication and module assembly process technologies required to meet the cost, lifetime, production capacity, and performance goals of the FSA Project. R&D efforts expended by Government, Industry, and Universities in developing processes capable of meeting the projects goals during volume production conditions are summarized. The cost goals allocated for processing were demonstrated by small volume quantities that were extrapolated by cost analysis to large volume production. To provide proper focus and coverage of the process development effort, four separate technology sections are discussed: surface preparation, junction formation, metallization, and module assembly.

Anterior Myocardial Territory May Replace the Heart as Organ at Risk in Intensity-Modulated Radiotherapy for Left-Sided Breast Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan Wenyong; Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan; Liu Dong

Purpose: We investigated whether the heart could be replaced by the anterior myocardial territory (AMT) as the organ at risk (OAR) in intensity-modulated radiotherapy (IMRT) of the breast for patients with left-sided breast cancer. Methods and Materials: Twenty-three patients with left-sided breast cancer who received postoperative radiation after breast-conserving surgery were studied. For each patient, we generated five IMRT plans including heart (H), left ventricle (LV), AMT, LV+AMT, and H+LV as the primary OARs, respectively, except both lungs and right breast, which corresponded to IMRT(H), IMRT(LV), IMRT(AMT), IMRT(LV+AMT), and IMRT(H+LV). For the planning target volumes and OARs, the parameters ofmore » dose-volume histograms were compared. Results: The homogeneity index, conformity index, and coverage index were not compromised significantly in IMRT(AMT), IMRT(LV) and IMRT(LV+ AMT), respectively, when compared with IMRT(H). The mean dose to the heart, LV, and AMT decreased 5.3-21.5% (p < 0.05), 19.9-29.5% (p < 0.05), and 13.3-24.5% (p < 0.05), respectively. Similarly, the low (e.g., V5%), middle (e.g., V20%), and high (e.g., V30%) dose-volume of the heart, LV, and AMT decreased with different levels. The mean dose and V10% of the right lung increased by 9.2% (p < 0.05) and 27.6% (p < 0.05), respectively, in IMRT(LV), and the mean dose and V5% of the right breast decreased significantly in IMRT(AMT) and IMRT(LV+AMT). IMRT(AMT) was the preferred plan and was then compared with IMRT(H+LV); the majority of dose-volume histogram parameters of OARs including the heart, LV, AMT, both lungs, and the right breast were not statistically different. However, the low dose-volume of LV increased and the middle dose-volume decreased significantly (p < 0.05) in IMRT(AMT). Also, those of the right lung (V10%, V15%) and right breast (V5%, V10%) decreased significantly (p < 0.05). Conclusions: The AMT may replace the heart as the OAR in left-sided breast IMRT after breast-conserving surgery to decrease the radiation dose to the heart.« less

Comparative analyses of the neuron numbers and volumes of the amygdaloid complex in old and new world primates.

PubMed

Carlo, C N; Stefanacci, L; Semendeferi, K; Stevens, C F

2010-04-15

The amygdaloid complex (AC), a key component of the limbic system, is a brain region critical for the detection and interpretation of emotionally salient information. Therefore, changes in its structure and function are likely to provide correlates of mood and emotion disorders, diseases that afflict a large portion of the human population. Previous gross comparisons of the AC in control and diseased individuals have, however, mainly failed to discover these expected correlations with diseases. We have characterized AC nuclei in different nonhuman primate species to establish a baseline for more refined comparisons between the normal and the diseased amygdala. AC nuclei volume and neuron number in 19 subdivisions are reported from 13 Old and New World primate brains, spanning five primate species, and compared with corresponding data from humans. Analysis of the four largest AC nuclei revealed that volume and neuron number of one component, the central nucleus, has a negative allometric relationship with total amygdala volume and neuron number, which is in contrast with the isometric relationship found in the other AC nuclei (for both neuron number and volume). Neuron density decreases across all four nuclei according to a single power law with an exponent of about minus one-half. Because we have included quantitative comparisons with great apes and humans, our conclusions apply to human brains, and our scaling laws can potentially be used to study the anatomical correlates of the amygdala in disorders involving pathological emotion processing. (c) 2009 Wiley-Liss, Inc.

Why does the lung hyperinflate?

PubMed

Ferguson, Gary T

2006-04-01

Patients with chronic obstructive pulmonary disease (COPD) often have some degree of hyperinflation of the lungs. Hyperinflated lungs can produce significant detrimental effects on breathing, as highlighted by improvements in patient symptoms after lung volume reduction surgery. Measures of lung volumes correlate better with impairment of patient functional capabilities than do measures of airflow. Understanding the mechanisms by which hyperinflation occurs in COPD provides better insight into how treatments can improve patients' health. Both static and dynamic processes can contribute to lung hyperinflation in COPD. Static hyperinflation is caused by a decrease in elasticity of the lung due to emphysema. The lungs exert less recoil pressure to counter the recoil pressure of the chest wall, resulting in an equilibrium of recoil forces at a higher resting volume than normal. Dynamic hyperinflation is more common and can occur independent of or in addition to static hyperinflation. It results from air being trapped within the lungs after each breath due to a disequilibrium between the volumes inhaled and exhaled. The ability to fully exhale depends on the degree of airflow limitation and the time available for exhalation. These can both vary, causing greater hyperinflation during exacerbations or increased respiratory demand, such as during exercise. Reversibility of dynamic hyperinflation offers the possibility for intervention. Use of bronchodilators with prolonged durations of action, such as tiotropium, can sustain significant reductions in lung inflation similar in effect to lung volume reduction surgery. How efficacy of bronchodilators is assessed may, therefore, need to be reevaluated.

High-volume resistance training session acutely diminishes respiratory muscle strength.

PubMed

Hackett, Daniel A; Johnson, Nathan A; Chow, Chin-Moi

2012-01-01

This study investigated the effect of a high-volume compared to a low-volume resistance training session on maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP). Twenty male subjects with resistance training experience (6.2 ± 3.2 y), in a crossover trial, completed two resistance training protocols (high-volume: 5 sets per exercise; low-volume: 2 sets per exercise) and a control session (no exercise) on 3 separate occasions. MIP and MEP decreased by 13.6% (p < 0.01) and 14.7% (p < 0.01) respectively from pre-session MIP and MEP, following the high-volume session. MIP and MEP were unaffected following the low-volume or the control sessions. MIP returned to pre-session values after 40 minutes, whereas MEP remained significantly reduced after 60 minutes post-session by 9.2% compared to pre-session (p < 0.01). The findings suggest that the high-volume session significantly decreased MIP and MEP post-session, implicating a substantially increased demand on the respiratory muscles and that adequate recovery is mandatory following this mode of training. Key pointsRespiratory muscular strength performance is acutely diminished following a high-volume whole-body resistance training session.Greater ventilatory requirements and generation of IAP during the high-volume resistance training session may have contributed to the increased demand placed on the respiratory muscles.Protracted return of respiratory muscular strength performance to baseline levels may have implications for individuals prior to engaging in subsequent exercise bouts.

Computerized tomography with 3-dimensional reconstruction for the evaluation of renal size and arterial anatomy in the living kidney donor.

PubMed

Janoff, Daniel M; Davol, Patrick; Hazzard, James; Lemmers, Michael J; Paduch, Darius A; Barry, John M

2004-01-01

Computerized tomography (CT) with 3-dimensional (3-D) reconstruction has gained acceptance as an imaging study to evaluate living renal donors. We report our experience with this technique in 199 consecutive patients to validate its predictions of arterial anatomy and kidney volumes. Between January 1997 and March 2002, 199 living donor nephrectomies were performed at our institution using an open technique. During the operation arterial anatomy was recorded as well as kidney weight in 98 patients and displacement volume in 27. Each donor had been evaluated preoperatively by CT angiography with 3-D reconstruction. Arterial anatomy described by a staff radiologist was compared with intraoperative findings. CT estimated volumes were reported. Linear correlation graphs were generated to assess the reliability of CT volume predictions. The accuracy of CT angiography for predicting arterial anatomy was 90.5%. However, as the number of renal arteries increased, predictive accuracy decreased. The ability of CT to predict multiple arteries remained high with a positive predictive value of 95.2%. Calculated CT volume and kidney weight significantly correlated (0.654). However, the coefficient of variation index (how much average CT volume differed from measured intraoperative volume) was 17.8%. CT angiography with 3-D reconstruction accurately predicts arterial vasculature in more than 90% of patients and it can be used to compare renal volumes. However, accuracy decreases with multiple renal arteries and volume comparisons may be inaccurate when the difference in kidney volumes is within 17.8%.

Conductive pathway on cotton fabric created using solution with silver organometallic compound

NASA Astrophysics Data System (ADS)

Campbell, Eric E.; He, Ruijian; Mayer, Michael

2017-10-01

A knitted cotton fabric is made conductive by thermal deposition of an organometallic silver compound (OSC). For the thermal process, the fabric was soaked with the OSC liquid and heated to 225 °C for 4 min. The cured state of the OSC is determined by the stabilization in the electrical resistance. The resulting silver metallization is shaped as nanoparticles and a continuous film. A typical resistance of a 10 cm  ×  1.5 cm metallized strip made with 1.9 ml OSC is 1.70 Ω. Various other resistance levels were achieved. A higher volume of OSC provided a lower electrical resistance for the metallized conductive path but increased its stiffness. Lower resistance was achieved by increasing the number of repeat coatings while keeping the OSC volume constant. The resistance decreased when the OSC coated fabric was elongated, an effect similar to negative piezoresistivity. A resistance of initially 0.34 Ω decreased to a minimum of 0.29 Ω at 10% elongation under repeated stretching and relaxation cycling. The metallization method reported here can be suitable for applications in the field know as technical textiles, electronic textiles (e-textiles), wearable electronics, functional garments, or smart fabrics.

Brain volume reduction after whole-brain radiotherapy: quantification and prognostic relevance.

PubMed

Hoffmann, Christian; Distel, Luitpold; Knippen, Stefan; Gryc, Thomas; Schmidt, Manuel Alexander; Fietkau, Rainer; Putz, Florian

2018-01-22

Recent studies have questioned the value of adding whole-brain radiotherapy (WBRT) to stereotactic radiosurgery (SRS) for brain metastasis treatment. Neurotoxicity, including radiation-induced brain volume reduction, could be one reason why not all patients benefit from the addition of WBRT. In this study, we quantified brain volume reduction after WBRT and assessed its prognostic significance. Brain volumes of 91 patients with cerebral metastases were measured during a 150-day period after commencing WBRT and were compared with their pretreatment volumes. The average daily relative change in brain volume of each patient, referred to as the "brain volume reduction rate," was calculated. Univariate and multivariate Cox regression analyses were performed to assess the prognostic significance of the brain volume reduction rate, as well as of 3 treatment-related and 9 pretreatment factors. A one-way analysis of variance was used to compare the brain volume reduction rate across recursive partitioning analysis (RPA) classes. On multivariate Cox regression analysis, the brain volume reduction rate was a significant predictor of overall survival after WBRT (P < 0.001), as well as the number of brain metastases (P = 0.002) and age (P = 0.008). Patients with a relatively favorable prognosis (RPA classes 1 and 2) experienced significantly less brain volume decrease after WBRT than patients with a poor prognosis (RPA class 3) (P = 0.001). There was no significant correlation between delivered radiation dose and brain volume reduction rate (P = 0.147). In this retrospective study, a smaller decrease in brain volume after WBRT was an independent predictor of longer overall survival. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

[Repeated body position change training can improve human head-down tilt tolerance].

PubMed

Wu, Bin; Wu, Ping; Xue, Yue-Ying; Liu, Xing-Hua; Wang, Yan-Lei; Jiang, Shi-Zhong

2008-02-01

To verify the hypothesis that repeated body position change training can improve human head-down tilt (HDT) tolerance. Six young healthy subjects were trained with repeated position change for 9 times and 11 days according to protocol of alternative head-down and head-up tilts, each time of training lasted for about 35 min. Their HDT tolerance (- 30 degrees/30 min) were determined before and after training. (1) Compared with the data before training, subjects' symptom scores during HDT test after training decreased significantly (6.00 +/- 3.79 vs 1.00 +/- 0.63, P < 0.05), magnitude of the decreased heart rate increased significantly (-0.6 +/- 2.5 vs -4.4 +/- 3.6, P < 0.01). (2) Before training, blood flow volume of internal jugular vein (IJV) during HDT decreased significantly and that of internal carotid artery (ICA) increased significantly at the beginning period of HDT compared with pre-HDT (P < 0.01), while blood flow volume of the common carotid artery (CCA) presented increasing trend. After training, there was no significant difference in blood flow volume of IJV between during HDT and pre-HDT, that of ICA and CCA presented decreasing trend in the final period of HDT compared with Pre-HDT. Repeated body position change training can improve human head-down tilt tolerance. And its main causation is that headward shift of blood volume is restrained to some extend during HDT after training.

Singing with reduced air sac volume causes uniform decrease in airflow and sound amplitude in the zebra finch.

PubMed

Plummer, Emily Megan; Goller, Franz

2008-01-01

Song of the zebra finch (Taeniopygia guttata) is a complex temporal sequence generated by a drastic change to the regular oscillations of the normal respiratory pattern. It is not known how respiratory functions, such as supply of air volume and gas exchange, are controlled during song. To understand the integration between respiration and song, we manipulated respiration during song by injecting inert dental medium into the air sacs. Increased respiratory rate after injections indicates that the reduction of air affected quiet respiration and that birds compensated for the reduced air volume. During song, air sac pressure, tracheal airflow and sound amplitude decreased substantially with each injection. This decrease was consistently present during each expiratory pulse of the song motif irrespective of the air volume used. Few changes to the temporal pattern of song were noted, such as the increased duration of a minibreath in one bird and the decrease in duration of a long syllable in another bird. Despite the drastic reduction in air sac pressure, airflow and sound amplitude, no increase in abdominal muscle activity was seen. This suggests that during song, birds do not compensate for the reduced physiological or acoustic parameters. Neither somatosensory nor auditory feedback mechanisms appear to effect a correction in expiratory effort to compensate for reduced air sac pressure and sound amplitude.

Effects of OPC-51803, a novel, nonpeptide vasopressin V2-receptor agonist, on micturition frequency in Brattleboro and aged rats.

PubMed

Nakamura, Shigeki; Hirano, Takahiro; Yamamura, Yoshitaka; Itoh, Shuji; Kondo, Kazumi; Mori, Toyoki; Kambe, Toshimi

2003-12-01

We assessed the effects of OPC-51803 ((5R)-2-[1-(2-chloro-4-(1-pyrrolidinyl)benzoyl)-2,3,4,5-tetrahydro-1H-1-benzazepin-5-yl]-N-isopropylacetamide), a nonpeptide vasopressin V(2)-receptor agonist, on micturition frequency in female homozygous Brattleboro rats (strain carries hereditary diabetes insipidus) and aged male Sprague-Dawley rats with polyuria. Female homozygous Brattleboro rats exhibited more diuresis and a larger micturition frequency over a 24-h period than did the heterozygous controls. In Brattleboro rats, an oral administration of OPC-51803 at 0.03 and 0.3 mg/kg significantly decreased urinary frequency and was accompanied by decreased urine volume. However, little effect was seen in the mean and maximal micturition volume. Aged male Sprague-Dawley rats (25-month-old) showed a significant increase in urine volume throughout a 0- to 24-h period compared with mature (6-month-old) rats. Orally administered OPC-51803 at 0.3 mg/kg decreased not only urine volume but also urinary frequency in aged rats. Furthermore, OPC-51803 prolonged the time prior to the first micturition. Therefore, OPC-51803 decreased micturition frequency in both rat species by reducing urine outflow. This suggests that the compound will be useful for treating micturition disorders that result in frequent micturition, such as that from polyuria, nocturnal polyuria, and some kinds of urinary incontinence.

Evaluation of the Effect of the Volume Throughput and Maximum Flux of Low-Surface-Tension Fluids on Bacterial Penetration of 0.2 Micron-Rated Filters during Process-Specific Filter Validation Testing.

PubMed

Folmsbee, Martha

2015-01-01

Approximately 97% of filter validation tests result in the demonstration of absolute retention of the test bacteria, and thus sterile filter validation failure is rare. However, while Brevundimonas diminuta (B. diminuta) penetration of sterilizing-grade filters is rarely detected, the observation that some fluids (such as vaccines and liposomal fluids) may lead to an increased incidence of bacterial penetration of sterilizing-grade filters by B. diminuta has been reported. The goal of the following analysis was to identify important drivers of filter validation failure in these rare cases. The identification of these drivers will hopefully serve the purpose of assisting in the design of commercial sterile filtration processes with a low risk of filter validation failure for vaccine, liposomal, and related fluids. Filter validation data for low-surface-tension fluids was collected and evaluated with regard to the effect of bacterial load (CFU/cm(2)), bacterial load rate (CFU/min/cm(2)), volume throughput (mL/cm(2)), and maximum filter flux (mL/min/cm(2)) on bacterial penetration. The data set (∼1162 individual filtrations) included all instances of process-specific filter validation failures performed at Pall Corporation, including those using other filter media, but did not include all successful retentive filter validation bacterial challenges. It was neither practical nor necessary to include all filter validation successes worldwide (Pall Corporation) to achieve the goals of this analysis. The percentage of failed filtration events for the selected total master data set was 27% (310/1162). Because it is heavily weighted with penetration events, this percentage is considerably higher than the actual rate of failed filter validations, but, as such, facilitated a close examination of the conditions that lead to filter validation failure. In agreement with our previous reports, two of the significant drivers of bacterial penetration identified were the total bacterial load and the bacterial load rate. In addition to these parameters, another three possible drivers of failure were also identified: volume throughput, maximum filter flux, and pressure. Of the data for which volume throughput information was available, 24% (249/1038) of the filtrations resulted in penetration. However, for the volume throughput range of 680-2260 mL/cm(2), only 9 out of 205 bacterial challenges (∼4%) resulted in penetration. Of the data for which flux information was available, 22% (212/946) resulted in bacterial penetration. However, in the maximum filter flux range from 7 to 18 mL/min/cm(2), only one out of 121 filtrations (0.6%) resulted in penetration. A slight increase in filter failure was observed in filter bacterial challenges with a differential pressure greater than 30 psid. When designing a commercial process for the sterile filtration of a low-surface-tension fluid (or any other potentially high-risk fluid), targeting the volume throughput range of 680-2260 mL/cm(2) or flux range of 7-18 mL/min/cm(2), and maintaining the differential pressure below 30 psid, could significantly decrease the risk of validation filter failure. However, it is important to keep in mind that these are general trends described in this study and some test fluids may not conform to the general trends described here. Ultimately, it is important to evaluate both filterability and bacterial retention of the test fluid under proposed process conditions prior to finalizing the manufacturing process to ensure successful process-specific filter validation of low-surface-tension fluids. An overwhelming majority of process-specific filter validation (qualification) tests result in the demonstration of absolute retention of test bacteria by sterilizing-grade membrane filters. As such, process-specific filter validation failure is rare. However, while bacterial penetration of sterilizing-grade filters during process-specific filter validation is rarely detected, some fluids (such as vaccines and liposomal fluids) have been associated with an increased incidence of bacterial penetration. The goal of the following analysis was to identify important drivers of process-specific filter validation failure. The identification of these drivers will possibly serve to assist in the design of commercial sterile filtration processes with a low risk of filter validation failure. Filter validation data for low-surface-tension fluids was collected and evaluated with regard to bacterial concentration and rates, as well as filtered fluid volume and rate (Pall Corporation). The master data set (∼1160 individual filtrations) included all recorded instances of process-specific filter validation failures but did not include all successful filter validation bacterial challenge tests. This allowed for a close examination of the conditions that lead to process-specific filter validation failure. As previously reported, two significant drivers of bacterial penetration were identified: the total bacterial load (the total number of bacteria per filter) and the bacterial load rate (the rate at which bacteria were applied to the filter). In addition to these parameters, another three possible drivers of failure were also identified: volumetric throughput, filter flux, and pressure. When designing a commercial process for the sterile filtration of a low-surface-tension fluid (or any other penetrative-risk fluid), targeting the identified bacterial challenge loads, volume throughput, and corresponding flux rates could decrease, and possibly eliminate, the risk of validation filter failure. However, it is important to keep in mind that these are general trends described in this study and some test fluids may not conform to the general trends described here. Ultimately, it is important to evaluate both filterability and bacterial retention of the test fluid under proposed process conditions prior to finalizing the manufacturing process to ensure successful filter validation of low-surface-tension fluids. © PDA, Inc. 2015.

A hypothesis of target cell formation in sickle cell disease.

PubMed

Wong, P

2016-08-01

A fraction of erythrocytes appear as target cells in stained blood smears in sickle cell disease, due to a inheritance of the hemoglobin variant Hb S, polymerizing upon deoxygenation. These cells appear in a three dimension as thin cups. A process of their formation in this disease is proposed based on a band 3-based mechanism of the erythrocyte shape control, able to explain the erythrocyte echinocytosis by glucose depletion. It indicates that their formation is due to a stomatocytogenic slow outward transport of the dibasic form of endogenous Pi with an H(+) by band 3, promoted by the decrease of the Donnan ratio, which decreases cell pH and volume, attributed by a decrease of cell KCl concentration by the higher efflux of K(+)Cl(-) cotransport and Ca(2+) activation of the Gardos channel. Its implications are briefly discussed with respect to target cells per se, target cell formation in other hemoglobinopathies, acquired and inherited disorders of the lipid metabolism and dehydrated hereditary stomatocytosis as well as a stomatocyte presence in a double heterozygote of Hb S and Hb C and of an involvement of the process of target cell formation in acanthocytosis in acquired and inherited disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mechanical Properties of TRIP Steel Microalloyed with Ti

NASA Astrophysics Data System (ADS)

Krizan, Daniel; De Cooman, Bruno C.

2014-07-01

The precipitation state, microstructure, retained austenite stability, and mechanical properties of cold-rolled Ti-microalloyed CMnAlSiP TRIP steel were investigated. The precipitation state was analyzed in each processing step by means of transmission electron microscopy, chemical analysis using the anodic dissolution method, and by model calculations. Ti additions refined the microstructure mainly by the pinning of austenite and ferrite grain boundaries by various Ti-containing precipitates. Ti additions also resulted in a refinement of the size of the retained austenite islands and caused a slight decrease of the volume fraction and carbon content of the retained austenite. The morphology of the retained austenite was also changed and the stability of the retained austenite decreased, but Ti addition still resulted in an adequate strength-ductility balance and a tensile strength close to 1 GPa.

High-Temperature Erosive Behavior of Plasma Sprayed Cr3C2-NiCr/Cenosphere Coating

NASA Astrophysics Data System (ADS)

Mathapati, Mahantayya; Doddamani, Mrityunjay; Ramesh, M. R.

2018-02-01

This research examines the deposition of Cr3C2-NiCr/cenosphere and Cr3C2-NiCr coatings on MDN 321 steel through the process of plasma spray. In this process, the solid particle erosion test is established at 200, 400, 600 °C with 30° and 90° impact angles. Alumina erodent is adopted to investigate the erosive behavior of the coating at higher temperatures. The properties of the Cr3C2-NiCr/cenosphere coating are established based on the microhardness, the adhesive strength, the fracture toughness, and the ductility. To quantify volume loss as a result of erosion, an optical profilometer is used. At higher temperature, decrease in the erosion volume loss of Cr3C2-NiCr/cenosphere and Cr3C2-NiCr coatings is observed. The erosion-resistive property of Cr3C2-NiCr/cenosphere coating is higher than that of MDN 321 steel by 76%. This property is influenced by high-temperature stability of mullite, alumina, and protective oxide layer that is formed at elevated temperatures. The morphology of eroded coating discloses a brittle mode of material removal.

Comparison of the effect of a single dose of erythromycin with pantoprazole on gastric content volume and acidity in elective general surgery patients

PubMed Central

Bhatia, Nidhi; Palta, Sanjeev; Arora, Kanika

2011-01-01

Introduction: Pulmonary aspiration of gastric contents remains one of the most feared complications of anesthesia. A gastric pH of 2.5 or less and a volume of 25 ml (0.4 ml/kg body weight) or more in average adult patients are considered critical factors for the development of pulmonary damage in adults. Materials and Methods: This study compared the efficacy of a single oral dose of erythromycin (a macrolide antibiotic) with oral pantoprazole (a proton pump inhibitor) on pre-operative gastric fluid volume and pH in a prospective, randomized, double-blind controlled fashion in 80 adult patients (of ASA physical status I and II) planned for elective surgery under general anesthesia. Patients were divided into two groups of 40 patients each. The pantoprazole group (Group I) received oral pantoprazole 40 mg and the erythromycin group (Group II) received oral erythromycin 250 mg at least 1 h prior to the induction of anesthesia. After tracheal intubation, gastric fluid was aspirated via a Salem Sump tube and its volume and pH were measured. Results: Although both erythromycin and pantoprazole decreased the gastric fluid volume to a similar extent, the decrease in gastric fluid acidity by pantoprazole was significantly greater than that by erythromycin. The proportion of patients at risk of pulmonary aspiration according to traditional criteria, i.e. pH ≤2.5 and volume ≥25ml, was lower in the pantoprazole group. Conclusion: Administration of pantoprazole was found to be more useful than a sub-therapeutic dose of erythromycin in decreasing both volume and acidity of gastric content. PMID:21772679

Preparation of activated petroleum coke for removal of naphthenic acids model compounds: Box-Behnken design optimization of KOH activation process.

PubMed

Niasar, Hojatallah Seyedy; Li, Hanning; Das, Sreejon; Kasanneni, Tirumala Venkateswara Rao; Ray, Madhumita B; Xu, Chunbao Charles

2018-04-01

This study employed Box-Behnken design and response surface methodology to optimize activation parameters for the production of activated petroleum coke (APC) adsorbent from petroleum coke (PC) to achieve highest adsorption capacity for three model naphthenic acids. Activated petroleum coke (APC) adsorbent with a BET surface area of 1726 m 2 /g and total pore volume of 0.85 cc/g was produced at the optimum activation conditions (KOH/coke mass ratio) of 3.0, activation temperature 790 °C, and activation time 3.47 h). Effects of the activation parameters on the adsorption pefromances (adsortion capaciy and kinetics) were investigated. With the APC obtained at the optimum activation condition, the maximum adsorption capacity of 451, 362, and 320 (mg/g) was achieved for 2-naphthoic acid, diphenylacetic acid and cyclohexanepentanoic acid (CP), respectively. Although, generally APC adsorbents with a higher specific surface area and pore volume provide better adsorption capacity, the textural properties (surface areas and pore volume) are not the only parameters determining the APC adsorbents' adsorption capacity. Other parameters such as surface functionalities play effective roles on the adsorption capacity of the produced APC adsorbents for NAs. The KOH activation process, in particular the acid washing step, distinctly reduced the sulfur and metals contents in the raw PC, decreasing the leaching potential of metals from APC adsorbents during adsorption. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cloud Optimized Image Format and Compression

NASA Astrophysics Data System (ADS)

Becker, P.; Plesea, L.; Maurer, T.

2015-04-01

Cloud based image storage and processing requires revaluation of formats and processing methods. For the true value of the massive volumes of earth observation data to be realized, the image data needs to be accessible from the cloud. Traditional file formats such as TIF and NITF were developed in the hay day of the desktop and assumed fast low latency file access. Other formats such as JPEG2000 provide for streaming protocols for pixel data, but still require a server to have file access. These concepts no longer truly hold in cloud based elastic storage and computation environments. This paper will provide details of a newly evolving image storage format (MRF) and compression that is optimized for cloud environments. Although the cost of storage continues to fall for large data volumes, there is still significant value in compression. For imagery data to be used in analysis and exploit the extended dynamic range of the new sensors, lossless or controlled lossy compression is of high value. Compression decreases the data volumes stored and reduces the data transferred, but the reduced data size must be balanced with the CPU required to decompress. The paper also outlines a new compression algorithm (LERC) for imagery and elevation data that optimizes this balance. Advantages of the compression include its simple to implement algorithm that enables it to be efficiently accessed using JavaScript. Combing this new cloud based image storage format and compression will help resolve some of the challenges of big image data on the internet.

Neural basis of major depressive disorder: Beyond monoamine hypothesis.

PubMed

Boku, Shuken; Nakagawa, Shin; Toda, Hiroyuki; Hishimoto, Akitoyo

2018-01-01

The monoamine hypothesis has been accepted as the most common hypothesis of major depressive disorder (MDD) for a long period because of its simplicity and understandability. Actually, most currently used antidepressants have been considered to act based on the monoamine hypothesis. However, an important problem of the monoamine hypothesis has been pointed out as follows: it fails to explain the latency of response to antidepressants. In addition, many patients with MDD have remained refractory to currently used antidepressants. Therefore, monoamine-alternate hypotheses are required to explain the latency of response to antidepressants. Such hypotheses have been expected to contribute to identifying hopeful new therapeutic targets for MDD. Past studies have revealed that the volume of the hippocampus is decreased in patients with MDD, which is likely caused by the failure of the hypothalamic-pituitary-adrenal axis and following elevation of glucocorticoids. Two hypotheses have been proposed to explain the volume of the hippocampus: (i) the neuroplasticity hypothesis; and (ii) the neurogenesis hypothesis. The neuroplasticity hypothesis explains how the hippocampal volume is decreased by the morphological changes of hippocampal neurons, such as the shortening length of dendrites and the decreased number and density of spines. The neurogenesis hypothesis explains how the hippocampal volume is decreased by the decrease of neurogenesis in the hippocampal dentate gyrus. These hypotheses are able to explain the latency of response to antidepressants. In this review, we first overview how the neuroplasticity and neurogenesis hypotheses have been developed. We then describe the details of these hypotheses. © 2017 The Authors. Psychiatry and Clinical Neurosciences © 2017 Japanese Society of Psychiatry and Neurology.

Transformation around intruders in granular media

NASA Astrophysics Data System (ADS)

Jop, Pierre; Merceron, Aymeric; Sauret, Alban

2017-06-01

Sintering, glass melting and other industrially relevant processes turn batches of grains into homogeneous products. Such processes involve coupled chemical and physical transformations of the granular packing. For sake of simplicity, we study how local evolutions on grains (volume decreases for example) entail mechanical rearrangements in the overall pile. Inert bidisperse metallic disks are mixed and confined in a vertical 2D cell. At the bottom of this set-up, initial intruders (one or two) have been previously set and mechanically linked to a linear motorized jack. While we quasi-statically pull the intruder(s) downward out of the cell at constant speed and constant liberated surface, we tracked the surrounding granular packing. Events largely distributed both spatially and temporally occur around intruders. We focus on the influence of the distance between the intruders on the local dynamic of the packing. We compare the distribution of the size of the event and their frequency as function of the relative position of the intruder, as a function of their radius. We show that their influence decreases rapidly. At short distance the mechanical perturbation induced by one intruder can destabilize the packing around the other.

Tidal volume single-breath washin of SF6 and CH4 in transient microgravity

NASA Technical Reports Server (NTRS)

Dutrieue, Brigitte; Paiva, Manuel; Verbanck, Sylvia; Le Gouic, Marine; Darquenne, Chantal; Prisk, G. Kim

2003-01-01

We performed tidal volume single-breath washins (SBW) by using tracers of different diffusivity and varied the time spent in microgravity (microG) before the start of the tests to look for time-dependent effects. SF(6) and CH(4) phase III slopes decreased by 35 and 26%, respectively, in microG compared with 1 G (P < 0.05), and the slope difference between gases disappeared. There was no effect of time in microG, suggesting that neither the hypergravity period preceding microG nor the time spent in microG affected gas mixing at volumes near functional residual capacity. In previous studies using SF(6) and He (Lauzon A-M, Prisk GK, Elliott AR, Verbanck S, Paiva M, and West JB. J Appl Physiol 82: 859-865, 1997), the vital capacity SBW showed an increase in slope difference between gases in transient microG, the opposite of the decrease in sustained microG. In contrast, tidal volume SBW showed a decrease in slope difference in both microG conditions. Because it is only the behavior of the more diffusive gas that differed between maneuvers and microG conditions, we speculate that, in the previous vital capacity SBW, the hypergravity period preceding the test in transient microG provoked conformational changes at low lung volumes near the acinar entrance.

Diffusion anisotropy in fresh and fixed prostate tissue ex vivo.

PubMed

Bourne, Roger M; Bongers, Andre; Chatterjee, Aritrick; Sved, Paul; Watson, Geoffrey

2016-08-01

To investigate diffusion anisotropy in whole human prostate specimens Seven whole radical prostatectomy specimens were obtained with informed patient consent and institutional ethics approval. Diffusion tensor imaging was performed at 9.4 Tesla. Diffusion tensors were calculated from the native acquired data and after progressive downsampling Fractional anisotropy (FA) decreased as voxel volume increased, and differed widely between prostates. Fixation decreased mean FA by ∼0.05-0.08 at all voxel volumes but did not alter principle eigenvector orientation. In unfixed tissue high FA (> 0.6) was found only in voxels of volume <0.5 mm(3) , and then only in a small fraction of all voxels. At typical clinical voxel volumes (4-16 mm(3) ) less than 50% of voxels had FA > 0.25. FA decreased at longer diffusion times (Δ = 60 or 80 ms compared with 20 ms), but only by ∼0.02 at typical clinical voxel volume. Peripheral zone FA was significantly lower than transition zone FA in five of the seven prostates FA varies widely between prostates. The very small proportion of clinical size voxels with high FA suggests that in clinical DWI studies ADC based on three-direction measurements will be minimally affected by anisotropy. Magn Reson Med 76:626-634, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Effect of new synthetic PEGylated ferulic acids in comparison with ferulic acid and commercial surfactants on the properties of wheat flour dough and bread.

PubMed

Nicks, François; Richel, Aurore; Dubrowski, Thomas; Wathelet, Bernard; Wathelet, Jean-Paul; Blecker, Christophe; Paquot, Michel

2013-08-15

Ferulic acid esterified with poly(ethylene glycol) with three different average molecular weights (200, 400 and 1000 g mol(-1)) was studied in bread-making. The effects of these antioxidants on the properties of wheat flour dough and bread were analysed and compared with those obtained with ferulic acid and two commercial surfactants, the diacetyl tartaric acid ester of mono- and diglycerides and sodium stearoyl lactylate. Farinographic and alveographic methods as well as weight, volume and bread firmness measurements were used for this purpose. Similar to ferulic acid, when the PEGylated derivatives were implemented in the dough (5000 ppm), it accelerated the breakdown of the dough and decreased its rheological properties. However, the important diminution of loaf volume, observed when dough supplemented with ferulic acid was baked, was avoided. That decrease in volume was related to the inhibition of the yeast (Saccharomyces cerevisae) by the unesterified ferulic acid. Moreover, two of the PEGylated ferulic acids even contributed to an increase of loaf volumes (5-6%) and demonstrated crumb softener properties. The addition of ferulic acid to wheat flour dough caused the inhibition of the yeast, which resulted in decreased bread volume. That effect could be avoid by the esterification of ferulic acid with poly(ethylene glycol). © 2013 Society of Chemical Industry.

Methylene Blue Ameliorates Ischemia/Reperfusion-Induced Cerebral Edema: An MRI and Transmission Electron Microscope Study.

PubMed

Fang, Qing; Yan, Xu; Li, Shaowu; Sun, Yilin; Xu, Lixin; Shi, Zhongfang; Wu, Min; Lu, Yi; Dong, Liping; Liu, Ran; Yuan, Fang; Yang, Shao-Hua

2016-01-01

The neuroprotective effect of methylene blue (MB) has been identified against various brain disorders, including ischemic stroke. In the present study, we evaluated the effects of MB on postischemic brain edema using magnetic resonance imaging (MRI) and transmission electron microscopy (TEM). Adult male rats were subjected to transient focal cerebral ischemia induced by 1 h middle cerebral artery occlusion (MCAO), followed by reperfusion. MB was infused intravenously immediately after reperfusion (3 mg/kg) and again at 3 h post-occlusion (1.5 mg/kg). Normal saline was administered as vehicle control. Sequential MRIs, including apparent diffusion coefficient (ADC) and T2-weighted imaging (T2WI), were obtained at 0.5, 2.5, and 48 h after the onset of stroke. Separated groups of animals were sacrificed at 2.5 and 48 h after stroke for ultrastructural analysis by TEM. In addition, final lesion volumes were analyzed by triphenyltetrazolium chloride (TTC) staining at 48 h after stroke. Ischemic stroke induced ADC lesion volume at 0.5 h during MCAOs that were temporally recovered at 1.5 h after reperfusion. No significant difference in ADC-defined lesion was observed between vehicle and MB treatment groups. At 48 h after stroke, MB significantly reduced ADC lesion and T2WI lesion volume and attenuated cerebral swelling. Consistently, MB treatment significantly decreased TTC-defined lesion volume at 48 h after stroke. TEM revealed remarkable swollen astrocytes, astrocytic perivascular end-feet, and concurrent shrunken neurons in the penumbra at 2.5 and 48 h after MCAO. MB treatment attenuated astrocyte swelling, the perivascular astrocytic foot process, and endothelium and also alleviated neuron degeneration. This study demonstrated that MB could decrease postischemic brain edema and provided additional evidence that future clinical investigation of MB for the treatment of ischemic stroke is warrented.

Trends in Coronary Revascularization and Ischemic Heart Disease-Related Mortality in Israel.

PubMed

Blumenfeld, Orit; Na'amnih, Wasef; Shapira-Daniels, Ayelet; Lotan, Chaim; Shohat, Tamy; Shapira, Oz M

2017-02-17

We investigated national trends in volume and outcomes of percutaneous coronary angioplasty (PCI), coronary artery bypass grafting (CABG), and ischemic heart disease-related mortality in Israel. Using International Classification of Diseases 9th and 10th revision codes, we linked 5 Israeli national databases, including the Israel Center for Disease Control National PCI and CABG Registries, the Ministry of Health Hospitalization Report, the Center of Bureau of Statistics, and the Ministry of Interior Mortality Report, to assess the annual PCI and CABG volume, procedural mortality, comorbidities, and ischemic heart disease-related mortality between 2002 and 2014. Trends over time were analyzed using linear regression, assuming a Poisson distribution. A total of 298 390 revascularization procedures (PCI: 255 724, CABG: 42 666) were performed during the study period. PCI volume increased by 9% from 2002 to 2008 (387.4/100 000 to 423.2/100 000), steadily decreasing by 10.5% to 378.5/100 000 in 2014 ( P =0.70 for the trend). CABG volume decreased by 59% (109.0/100 000 to 45.2/100 000) from 2002 to 2013, leveling at 46.4/100 000 ( P <0.0001). PCI/CABG ratio increased from 3.6 in 2002 to 8.5 in 2013, slightly decreasing to 8.2 by 2014 ( P <0.0001). In-hospital procedural mortality remained stable (PCI: 1.2-1.6%, P =0.34, CABG: 3.7-4.4%, P =0.29) despite a significant change in patient clinical profile. During the course of the study, ischemic heart disease-related mortality decreased by 46% (84.6-46/100 000, P <0.001). We observed a dramatic change in coronary revascularization procedures type and volume, and a marked decrease in ischemic heart disease-related mortality in Israel. The reasons for the observed changes remain unclear and need to be further investigated. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Dose-related cerebellar abnormality in rats with prenatal exposure to X-irradiation by magnetic resonance imaging volumetric analysis.

PubMed

Sawada, Kazuhiko; Saito, Shigeyoshi; Horiuchi-Hirose, Miwa; Mori, Yuki; Yoshioka, Yoshichika; Murase, Kenya

2013-09-01

Cerebellar abnormalities in 4-week-old rats with a single whole body X-irradiation at a dose of 0.5, 1.0, or 1.5 Gy on embryonic day (ED) 15 were examined by magnetic resonance imaging (MRI) volumetry. A 3D T2 W-MRI anatomical sequence with high-spatial resolution at 11.7-tesla was acquired from the fixed rat heads. By MRI volumetry, whole cerebellar volumes decreased dose-dependently. Multiple linear regression analysis revealed that the cortical volume (standardized β=0.901; P<0.001) was a major explanatory variable for the whole cerebellar volume, whereas both volumes of the white matter and deep cerebellar nuclei also decreased depending on the X-irradiation dose. The present MRI volumetric analysis revealed a dose-related cerebellar cortical hypoplasia by prenatal exposure to X-irradiation on E15. © 2013 The Authors. Congenital Anomalies © 2013 Japanese Teratology Society.

Single Mode Air-Clad Single Crystal Sapphire Optical Fiber

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hill, Cary; Homa, Dan; Yu, Zhihao

The observation of single mode propagation in an air-clad single crystal sapphire optical fiber at wavelengths at and above 783 nm is presented for the first time. A high-temperature wet acid etching method was used to reduce the diameter of a 10 cm length of commercially-sourced sapphire fiber from 125 micrometers to 6.5 micrometers, and far-field imaging provided modal information at intervals as the fiber diameter decreased. Modal volume was shown to decrease with decreasing diameter, and single mode behavior was observed at the minimum diameter achieved. While weakly-guiding approximations are generally inaccurate for low modal volume optical fiber withmore » high core-cladding refractive index disparity, consistency between these approximations and experimental results was observed when the effective numerical aperture was measured and substituted for the theoretical numerical aperture in weakly-guiding approximation calculations. With the demonstration of very low modal volume in sapphire at fiber diameters much larger than anticipated by legacy calculations, the resolution of sapphire fiber distributed sensors may be increased and other sensing schemes requiring very low modal volume, such as fiber Bragg gratings, may be realized in extreme environment applications.« less

Effects of concentration, temperature and solvent composition on density and apparent molar volume of the binary mixtures of cationic-anionic surfactants in methanol-water mixed solvent media.

PubMed

Bhattarai, Ajaya; Chatterjee, Sujeet Kumar; Niraula, Tulasi Prasad

2013-01-01

The accurate measurements on density of the binary mixtures of cetyltrimethylammonium bromide and sodium dodecyl sulphate in pure water and in methanol(1) + water (2) mixed solvent media containing (0.10, 0.20, and 0.30) volume fractions of methanol at 308.15, 318.15, and 323.15 K are reported. The concentrations are varied from (0.03 to 0.12) mol.l(-1) of sodium dodecyl sulphate in presence of ~ 5.0×10(-4) mol.l(-1) cetyltrimethylammonium bromide. The results showed almost increase in the densities with increasing surfactant mixture concentration, also the densities are found to decrease with increasing temperature over the entire concentration range, investigated in a given mixed solvent medium and these values are found to decrease with increasing methanol content in the solvent composition. The concentration dependence of the apparent molar volumes appear to be negligible over the entire concentration range, investigated in a given mixed solvent medium and the apparent molar volumes increase with increasing temperature and are found to decrease with increasing methanol content in the solvent composition.

Comparison of Echocardiographic Measurements Before and After Short and Long Duration Spaceflight

NASA Technical Reports Server (NTRS)

Fritsch-Yelle, Janice M.; South, Donna A.; Wood, Margie L.; Bungo, Michael W.

2000-01-01

Previous echocardiography studies in astronauts before and after short duration (4 - 17 days) missions have demonstrated a decrease in resting left ventricular (LV) stroke volume (SV), but maintained ejection fraction (EF) and cardiac output. Similar studies before and after long duration (129 - 144 days) spaceflight have been rare and their overall results equivocal. The purpose of this work was to compare the echocardiographic measurements (M-mode, 2-D and Doppler) from short duration (n = 13) and long duration (n = 4) crewmembers. Compared to short duration astronauts, long duration crewmembers had a significantly greater percent decrease in EF (+6+/-0.02 vs.-10.5+/-0.03, p = 0.005) and percent fractional shortening (+7+/-0.03 vs. -11+/-0.07, p = 0.0 15), and an increase in LV end systolic volume (-12+/-0.06 vs. +39+/-0.24, p = 0.011). These data suggest a reduction in cardiac function that relates to mission duration. As the changes in blood pressure and circulating blood volume (9% - 12%) are reported to be similar after short and long duration flights, the drop in EF after longer spaceflights is likely due to a decrease in cardiac function rather than altered blood volume.

Single Mode Air-Clad Single Crystal Sapphire Optical Fiber

DOE PAGES

Hill, Cary; Homa, Dan; Yu, Zhihao; ...

2017-05-03

The observation of single mode propagation in an air-clad single crystal sapphire optical fiber at wavelengths at and above 783 nm is presented for the first time. A high-temperature wet acid etching method was used to reduce the diameter of a 10 cm length of commercially-sourced sapphire fiber from 125 micrometers to 6.5 micrometers, and far-field imaging provided modal information at intervals as the fiber diameter decreased. Modal volume was shown to decrease with decreasing diameter, and single mode behavior was observed at the minimum diameter achieved. While weakly-guiding approximations are generally inaccurate for low modal volume optical fiber withmore » high core-cladding refractive index disparity, consistency between these approximations and experimental results was observed when the effective numerical aperture was measured and substituted for the theoretical numerical aperture in weakly-guiding approximation calculations. With the demonstration of very low modal volume in sapphire at fiber diameters much larger than anticipated by legacy calculations, the resolution of sapphire fiber distributed sensors may be increased and other sensing schemes requiring very low modal volume, such as fiber Bragg gratings, may be realized in extreme environment applications.« less

Alterations in left ventricular volumes induced by Valsalva manoeuvre

NASA Technical Reports Server (NTRS)

Brooker, J. Z.; Alderman, E. L.; Harrison, D. C.

1974-01-01

Five patients were studied with left ventriculography during different phases of the Valsalva manoeuvre. Small doses of contrast medium allowed adequate repetitive visualization of the left ventricle for volume calculation. During strain phase, the volume of the left ventricle decreased by nearly 50 per cent in each case, and stroke volume and cardiac output also dropped strikingly. Release of straining was attended by a sharp rebound of left ventricular volume to control levels, with a transient surge of increased cardiac output 42 per cent above that of the resting state.

Possibility of deuterium free water using as antitumoral means with reference to conditions of Martian expedition

NASA Astrophysics Data System (ADS)

Sinyak, Y.; Turusov, V.; Grigroriev, A.; Yaridze, D.; Gaidadimov, V.; Antoshina, E.; Gorkova, T.; Truhanova, L.

The interplanetary space flights, Martian program as an example, will take place under conditions of increasing radiation level on crew. The search of methods for a decrease of oncologic risk produced by irradiation of astronauts, is one of the major factors of a successful implementation of a flight program. One of such methods is a usage by crew of potable water with the reduced concentrations of a heavy stable isotope of hydrogen - deuterium, which can be obtained in the regenerative life support systems. The heavy water (D2O) has toxic properties, distorting biochemical reactions in the cell, inhibiting process of DNA replication. It can be presumed that the replacement of deuterium in the water for protium will result in normalization of cell metabolism, reparation will take place and this will lead to the inhibition of tumour development. In this study the water with a decreased by 65% of deuterium was used. Antitumour properties of D 2-free water were studied with transplantable Lewis lung carcinoma in BDF1 strain of mice. First results show that average time of appearance of the first nodules at the site of transplantation was 14 % longer in mice fed D 2-free water as compared to control. The tumour volume in the experimental group (decreased content of D2 ) was always lower than in the control. Statistically significant differences in the tumour volume were registered at the 13, 15, 23, 26 and 28 -th days after transplantation. Inhibition of tumour growth was equal to 100% and 51% at the 5 th and 15-th days after- transplantation respectively. Increase of life span in the experimental group was 10%. The results indicate that the use by astronauts of water with decreased content of deuterium may decrease the risk of oncological diseases under conditions of high radiation level in the flight to Mars.

Brain intra- and extracellular sodium concentration in multiple sclerosis: a 7 T MRI study.

PubMed

Petracca, Maria; Vancea, Roxana O; Fleysher, Lazar; Jonkman, Laura E; Oesingmann, Niels; Inglese, Matilde

2016-03-01

Intra-axonal accumulation of sodium ions is one of the key mechanisms of delayed neuro-axonal degeneration that contributes to disability accrual in multiple sclerosis. In vivo sodium magnetic resonance imaging studies have demonstrated an increase of brain total sodium concentration in patients with multiple sclerosis, especially in patients with greater disability. However, total sodium concentration is a weighted average of intra- and extra-cellular sodium concentration whose changes reflect different tissue pathophysiological processes. The in vivo, non-invasive measurement of intracellular sodium concentration is quite challenging and the few applications in patients with neurological diseases are limited to case reports and qualitative assessments. In the present study we provide first evidence of the feasibility of triple quantum filtered (23)Na magnetic resonance imaging at 7 T, and provide in vivo quantification of global and regional brain intra- and extra-cellular sodium concentration in 19 relapsing-remitting multiple sclerosis patients and 17 heathy controls. Global grey matter and white matter total sodium concentration (respectively P < 0.05 and P < 0.01), and intracellular sodium concentration (both P < 0.001) were higher while grey matter and white matter intracellular sodium volume fraction (indirect measure of extracellular sodium concentration) were lower (respectively P = 0.62 and P < 0.001) in patients compared with healthy controls. At a brain regional level, clusters of increased total sodium concentration and intracellular sodium concentration and decreased intracellular sodium volume fraction were found in several cortical, subcortical and white matter regions when patients were compared with healthy controls (P < 0.05 family-wise error corrected for total sodium concentration, P < 0.05 uncorrected for multiple comparisons for intracellular sodium concentration and intracellular sodium volume fraction). Measures of total sodium concentration and intracellular sodium volume fraction, but not measures of intracellular sodium concentration were correlated with T2-weighted and T1-weighted lesion volumes (0.05 < P < 0.01) and with Expanded Disability Status Scale (P < 0.05). Thus, suggesting that while intracellular sodium volume fraction decrease could reflect expansion of extracellular space due to tissue loss, intracellular sodium concentration increase could reflect neuro-axonal metabolic dysfunction. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Enabling aqueous processing for crack-free thick electrodes

DOE PAGES

Du, Zhijia; Rollag, K. M.; Li, J.; ...

2017-04-14

Aqueous processing of thick electrodes for Li-ion cells promises to increase energy density due to increased volume fraction of active materials, and to reduce cost due to the elimination of the toxic solvents. Here in this paper this work reports the processing and characterization of aqueous processed electrodes with high areal loading and associated full pouch cell performance. Cracking of the electrode coatings becomes a critical issue for aqueous processing of the positive electrode as areal loading increases above 20–25 mg/cm 2 (~4 mAh/cm 2). Crack initiation and propagation, which was observed during drying via optical microscopy, is related tomore » the build-up of capillary pressure during the drying process. The surface tension of water was reduced by the addition of isopropyl alcohol (IPA), which led to improved wettability and decreased capillary pressure during drying. The critical thickness (areal loading) without cracking increased gradually with increasing IPA content. The electrochemical performance was evaluated in pouch cells. Electrodes processed with water/IPA (80/20 wt%) mixture exhibited good structural integrity with good rate performance and cycling performance.« less

Novel Real-Time Diagnosis of the Freezing Process Using an Ultrasonic Transducer

PubMed Central

Tseng, Yen-Hsiang; Cheng, Chin-Chi; Cheng, Hong-Ping; Lee, Dasheng

2015-01-01

The freezing stage governs several critical parameters of the freeze drying process and the quality of the resulting lyophilized products. This paper presents an integrated ultrasonic transducer (UT) in a stainless steel bottle and its application to real-time diagnostics of the water freezing process. The sensor was directly deposited onto the stainless steel bottle using a sol-gel spray technique. It could operate at temperature range from −100 to 400 °C and uses an ultrasonic pulse-echo technique. The progression of the freezing process, including water-in, freezing point and final phase change of water, were all clearly observed using ultrasound. The ultrasonic signals could indicate the three stages of the freezing process and evaluate the cooling and freezing periods under various processing conditions. The temperature was also adopted for evaluating the cooling and freezing periods. These periods increased with water volume and decreased with shelf temperature (i.e., speed of freezing). This study demonstrates the effectiveness of the ultrasonic sensor and technology for diagnosing and optimizing the process of water freezing to save energy. PMID:25946629

Association of Changes in Abdominal Fat Quantity and Quality With Incident Cardiovascular Disease Risk Factors.

PubMed

Lee, Jane J; Pedley, Alison; Hoffmann, Udo; Massaro, Joseph M; Fox, Caroline S

2016-10-04

Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) are associated with adverse cardiometabolic risk profiles. This study explored the degree to which changes in abdominal fat quantity and quality are associated with changes in cardiovascular disease (CVD) risk factors. Study participants (n = 1,106; 44.1% women; mean baseline age 45.1 years) were drawn from the Framingham Heart Study Third Generation cohort who participated in the computed tomography (CT) substudy Exams 1 and 2. Participants were followed for 6.1 years on average. Abdominal adipose tissue volume in cm(3) and attenuation in Hounsfield units (HU) were determined by CT-acquired abdominal scans. The mean fat volume change was an increase of 602 cm(3) for SAT and an increase of 703 cm(3) for VAT; the mean fat attenuation change was a decrease of 5.5 HU for SAT and an increase of 0.07 HU for VAT. An increase in fat volume and decrease in fat attenuation were associated with adverse changes in CVD risk factors. An additional 500 cm(3) increase in fat volume was associated with incident hypertension (odds ratio [OR]: 1.21 for SAT; OR: 1.30 for VAT), hypertriglyceridemia (OR: 1.15 for SAT; OR: 1.56 for VAT), and metabolic syndrome (OR: 1.43 for SAT; OR: 1.82 for VAT; all p < 0.05). Similar trends were observed for each additional 5 HU decrease in abdominal adipose tissue attenuation. Most associations remained significant even after further accounting for body mass index change, waist circumference change, or respective abdominal adipose tissue volumes. Increasing accumulation of fat quantity and decreasing fat attenuation are associated with worsening of CVD risk factors beyond the associations with generalized adiposity, central adiposity, or respective adipose tissue volumes. Published by Elsevier Inc.

Blood volume and orthostatic responses of men and women to a 13-day bedrest

NASA Technical Reports Server (NTRS)

Fortney, S.; Driscoll, T.; Steinmann, L.; Alfrey, C.

1992-01-01

Changes in blood volume during space flight are thought to contribute to decrements in postflight orthostatic function. The purpose of this study was to determine whether gender affects red cell mass and plasma volume during a short exposure to simulated microgravity, and whether gender differences in orthostatic tolerance ensure. Methods: Ten men (31.5 plus or minus 5.2 years, STD) and eleven normally menstruating women (33.3) plus or minus 6.0 STD) underwent 13 days of 6 degree head-down bedrest. Plasma volume (Iodine 125 labeled human serum albumin) and red cell mass (Carbon 51 labeled red blood cells) were measured before bedrest and on bedrest day 13. On the same days, orthostatic tolerance (OT) was determined as the maximal pressure during a presyncopalimited lower body negative pressure test. Results: Plasma volume (PV) and red cell mass (RCM) decreased in both groups with a greater PV decrease (P less than 0.05) in men (6.3 plus or minus 0.7 ml/kg) than in women (4.1 plus or minus 0.6 ml/kg). Decreases in red cell mass were similar (1.7 plus or minus 0.2 ml/kg in men and 1.7 plus or minus 0.2 ml/kg in women). OT was similar for men and women before bedrest (minus 78 plus or minus 6 mmHg in men versus minus 70 plus or minus 4 mmHg in women) and decreased by a similar degree (by an average of 11 mmHg in both groups) after bedrest. The changes in OT did not correlate with changes in plasma volume during bedrest (r(exp 2) = 0.002). Conclusion: Thus, although female hormones may protect PV during bedrest, they do no appear to offer an advantage in terms of loss of orthostatic function.

The analysis of the process in the cooling tower with the low efficiency

NASA Astrophysics Data System (ADS)

Badriev, A. I.; Sharifullin, V. N.

2017-11-01

We put quite a difficult task maintaining a temperature drop to 11-12 degrees at thermal power plants to ensure the required depth of cooling of vacuum in the condenser, cooling towers. This requirement is achieved with the reducing of the hydraulic load with the low efficiency of the apparatus. The task analysis process in this unit and identify the causes of his poor performance was put in the work. One of the possible reasons may be the heterogeneity of the process in the volume of the apparatus. Therefore, it was decided to investigate experimentally the distribution of the irrigation water and the air flow in the cross section of industrial cooling towers. As a result, we found a significant uneven distribution of flows of water and air in the volume of the apparatus. We have shown theoretically that the uneven distribution of irrigation leads to a significant decrease in the efficiency of evaporation in the cooling tower. The velocity distribution of the air as the tower sections, and inside sections are interesting. The obtained experimental data allowed to establish the internal communication: the effects of the distributions of the density of irrigation in sections of the apparatus for the distribution of changes of the temperature and the air velocity. The obtained results allowed to formulate a methodology for determining process problems and to develop actions on increase of the efficiency of the cooling tower.

Theoretical test of Jarzynski's equality for reversible volume-switching processes of an ideal gas system.

PubMed

Sung, Jaeyoung

2007-07-01

We present an exact theoretical test of Jarzynski's equality (JE) for reversible volume-switching processes of an ideal gas system. The exact analysis shows that the prediction of JE for the free energy difference is the same as the work done on the gas system during the reversible process that is dependent on the shape of path of the reversible volume-switching process.

Effect of spray volume on the deposition, viability and infectivity of entomopathogenic nematodes in a foliar spray on vegetables.

PubMed

Brusselman, Eva; Beck, Bert; Pollet, Sabien; Temmerman, Femke; Spanoghe, Pieter; Moens, Maurice; Nuyttens, David

2012-10-01

Spray volume can influence the amount of free water on the leaf surface and subsequently the ability of entomopathogenic nematodes (EPNs) to move. In this study, an investigation was made of the effect of spray volume (548, 730 and 1095 L ha(-1) ) on the deposition, viability and infectivity of EPNs against Galleria mellonella on savoy cabbage, cauliflower and leek. Increasing spray volume decreased nematode deposition on 7.1 cm2 leek leaf discs at a 15° angle with the spray nozzle. Although the number of living nematodes observed on leek after 240 min of exposure was not significantly different between the low-volume application (548 L ha(-1) ) and the high-volume application (1095 L ha(-1) ), a greater infectivity was obtained in the latter application. The higher number of droplets deposited on the leek discs in the high-volume application may have stimulated nematode movement. No significant effect of spray volume was observed on the relative deposition of Steinernema carpocapsae on the bottom side of cauliflower and savoy cabbage leaf discs. In spite of the low S. carpocapsae deposition on the bottom side of the savoy cabbage discs, high infectivity was obtained against G. mellonella. Using the lowest spray volume on savoy cabbage, infectivity decreased with increasing exposure time, while infectivity was not affected by exposure time when a spray volume of 730 L ha(-1) or more was used. Spray volume is an important application parameter, as it affects nematode infectivity. Future research should investigate the effect of spray volume in the field and its influence on the effect of adjuvants. Copyright © 2012 Society of Chemical Industry.

Effect of mannitol on globe and orbital volumes in humans.

PubMed

Weber, Adam C; Blandford, Alexander D; Costin, Bryan R; Perry, Julian D

2018-03-01

To determine the effect of intravenous mannitol on globe and orbital volumes. Retrospective chart review of a consecutive series of Cleveland Clinic Neurosurgical Intensive Care Unit patients who underwent computed tomographic imaging before and after intravenous mannitol administration. Volume measurements were performed according to a previously described technique by averaging axial image areas. Measurements before and after mannitol administration were compared using paired t-test. Fourteen patients (28 eyes) met inclusion criteria. Average globe volume decreased 186 mm 3 (-2.5%, p = 0.02) after mannitol administration, while average orbital volume increased 353 mm 3 (+3.5%, p = 0.04). Average globe volume change for subjects with follow-up scan less than 4.7 hours (mean 1.9 hours; range 0.2-4.5 hours) after mannitol administration was -125 mm 3 (-1.7%, p = 0.24) and average orbital volume change was +458 mm 3 (+5.1%, p = 0.11). Average globe volume change after mannitol administration for those with follow-up more than 4.7 hours (average 13.9 hours, range 4.9-24.7 hours) was -246 mm 3 (-3.3%, p = 0.05) and orbital volume change was +248 mm 3 (+2.2%, p = 0.24). Dividing the study population into groups based on mannitol dose did not yield any statistically significant change. Human globe volume decreases after intravenous mannitol administration, while orbital volume increases. These volume changes occur during the time period when intraocular pressure normalizes, after the pressure-lowering effects of the drug. This novel volumetric information improves our understanding of mannitol's mechanism of action and its effects on human ocular and periocular tissues.

Mortality differences by surgical volume among patients with stomach cancer: a threshold for a favorable volume-outcome relationship.

PubMed

Choi, Hyeok; Yang, Seong-Yoon; Cho, Hee-Seung; Kim, Woorim; Park, Eun-Cheol; Han, Kyu-Tae

2017-07-17

Many studies have assessed the volume-outcome relationship in cancer patients, but most focused on better outcomes in higher volume groups rather than identifying a specific threshold that could assist in clinical decision-making for achieving the best outcomes. The current study suggests an optimal volume for achieving good outcome, as an extension of previous studies on the volume-outcome relationship in stomach cancer patients. We used National Health Insurance Service (NHIS) Sampling Cohort data during 2004-2013, comprising healthcare claims for 2550 patients with newly diagnosed stomach cancer. We conducted survival analyses adopting the Cox proportional hazard model to investigate the association of three threshold values for surgical volume of stomach cancer patients for cancer-specific mortality using the Youden index. Overall, 17.10% of patients died due to cancer during the study period. The risk of mortality among patients who received surgical treatment gradually decreased with increasing surgical volume at the hospital, while the risk of mortality increased again in "high" surgical volume hospitals, resulting in a j-shaped curve (mid-low = hazard ratio (HR) 0.773, 95% confidence interval (CI) 0.608-0.983; mid-high = HR 0.541, 95% CI 0.372-0.788; high = HR 0.659, 95% CI 0.473-0.917; ref = low). These associations were especially significant in regions with unsubstantial surgical volumes and less severe cases. The optimal surgical volume threshold was about 727.3 surgical cases for stomach cancer per hospital over the 1-year study period in South Korea. However, such positive effects decreased after exceeding a certain volume of surgeries.

Effect of simulated weightlessness on exercise-induced anaerobic threshold

NASA Technical Reports Server (NTRS)

Convertino, V. A.; Karst, G. M.; Kirby, C. R.; Goldwater, D. J.

1986-01-01

The effect of simulated weightlessness, induced by ten days of continuous bedrest (BR) in the -6 deg head-down position, on the exercise-induced anaerobic threshold (AT) was determined by comparing specific ventilatory and gas-exchange measurements during an incremental ergometer test performed before and after BR. The primary index for determining the exercise-induced AT values of each subject was visual identification of the workrate or oxygen uptake (VO2) at which the ratio of the expired minute ventilation volume (VE) to VO2 exhibited a systematic increase without a concomitant increase in the VE/VCO2 value. Following BR, the mean VO2max of the subjects decreased by 7.0 percent, and the AT decreased from a mean of 1.26 L/min VO2 before BR to 0.95 L/min VO2 after BR. The decrease in AT was manifested by a decrease in both absolute and relative workrates. The change in AT correlated significantly with the change in plasma volume but not with the change in VO2max. The results suggest that the reduction in AT cannot be completely explained by the reduction in VO2, and that the AT decrease is associated with the reduction in intravascular fluid volume.

Maximum static inspiratory and expiratory pressures with different lung volumes

PubMed Central

Lausted, Christopher G; Johnson, Arthur T; Scott, William H; Johnson, Monique M; Coyne, Karen M; Coursey, Derya C

2006-01-01

Background Maximum pressures developed by the respiratory muscles can indicate the health of the respiratory system, help to determine maximum respiratory flow rates, and contribute to respiratory power development. Past measurements of maximum pressures have been found to be inadequate for inclusion in some exercise models involving respiration. Methods Maximum inspiratory and expiratory airway pressures were measured over a range of lung volumes in 29 female and 19 male adults. A commercial bell spirometry system was programmed to occlude airflow at nine target lung volumes ranging from 10% to 90% of vital capacity. Results In women, maximum expiratory pressure increased with volume from 39 to 61 cmH2O and maximum inspiratory pressure decreased with volume from 66 to 28 cmH2O. In men, maximum expiratory pressure increased with volume from 63 to 97 cmH2O and maximum inspiratory pressure decreased with volume from 97 to 39 cmH2O. Equations describing pressures for both sexes are: Pe/Pmax = 0.1426 Ln( %VC) + 0.3402 R2 = 0.95 Pi/Pmax = 0.234 Ln(100 - %VC) - 0.0828 R2 = 0.96 Conclusion These results were found to be consistent with values and trends obtained by other authors. Regression equations may be suitable for respiratory mechanics models. PMID:16677384